What does y= when x = -1?
Two numbers have a sum of 18. Their product is 72. Find the numbers
Answer:
Step-by-step explanation:
x + y = 18
y = 18 - x
xy = 72
x(18 - x) = 72
-x² + 18x = 72
0 = 72 - 18x + x²
x = (18 ± √(18² - 4(1)(72))) / (2(1))
x = (18 ± 6)/2
x = 12
x = 6
Solve this quadratic equation by factorisation:
2y² + 4y – 30 = 0
my answer is
(2y+6)×(y-5)
2y+6=0 or y-5=0
y=-3 or y=5
is that correct?
Answer:
Y=5 y=-3
Step-by-step explanation:
Two real solutions:
y =(2+√64)/2=1+4= 5.000
or:
y =(2-√64)/2=1-4= -3.000
A housepainter mixed 5 gal of blue paint with every 9 gal of yellow paint in order to make a
green paint. Which ratio of gallons of blue paint to gallons of yellow paint will make the same
shade of green paint?
I think any of these would work
10;18
15;28
20;35
Answer:
5:9
Step-by-step explanation:
To Find:
ratio of yellow paint to blue paint to make a particular shade of green.
Solution:
The ratio can be written as 5 to 9, or 5:9
We know that if we mix 5 gallons of blue paint with 9 gallons of yellow paint we get the particular shade of green that we want.
Then the ratio of gallons of blue paint to gallons of yellow paint is 5 to 9, or 5:9
Meaning that for every 5 gallons of blue paint we need 9 of yellow paint.
Flip a coin three times. You will win $2 for each heads. What is the expected winning (expectation of your winning)
The three coins could land any these 8 ways:
HHH, HHT, HTH, HTT, THH, THT, TTH, TTT
P(3 heads) = 1 way out of 8 or 1/8
P(2 heads) = 3 ways out of 8 or 3/8
P(1 head) = 3 ways out of 8 or 3/8
P(0 heads) = 1 way out of 8 or 1/8
x=Winnings P(x) E(x)=x�P(x)
$3 1/8 $.375
$2 3/8 $.75
$1 3/8 $.375
-$10 1/8 -$1.25
---------------------------
Total expectation = $ .25
Determine whether the points p1 (6,9,7), p2(9,2,0), and p3(12,-5,-6) lie on the same line
Answer:
They are not.
Step-by-step explanation:
Let's first calculate the vectors joining the first point to the second and the first to the third, they will be useful later.
[tex]\vec v_1_2 = \vec P_2 -\vec P_1 = <3; -7; -7>\\\vec v_1_3= \vec P_2 -\vec P_1 = <6; -14; -13>[/tex]
At this point we have at least three options:
Write down the line between P1 and P2 in vector form, and then see if we can fit the third point in there.
Calculate the cross product between the two, if it's non-zero the three point are not in a line.
Try to determine the plane passing for the 3 points: if we find one they are not in a line.
Option 1:
The vector form of the lne between the firs two points is [tex]<6+3t;9-7t;7-7t>[/tex]. Let's check the coordinates of the third point:
[tex]x_3:\ 6+3t= 12 \rightarrow t=2\\y_3:\ 9-7t = -5 \rightarrow t =2\\7z_3:\ 7-7t=-6 \rightarrow t = 13/7\ne 2[/tex]
So the three points are not in a line.
Option 2:
Let's calculate the cross product of the two vectors we found at the beginning.
[tex]\vec v_1_2 \times \vec v_1_3 = det \left[\begin{array}{ccc}\hat i&\hat j&\hat k\\3&-7&-7\\6&-14&-13\end{array}\right] = \hat i [-7(-13)-(-14)(-7)] - \hat j[3(-13)-6(-7)]+\hat k [3(-14)-6(-7)] = 7\hat i -3 \hat j + 0 \hat k \ne 0[/tex]
Since the result is not the null vector, the three points are not in a line.
Option 3:
Let's write the plane (in the [tex]z= ax+by+c[/tex] form that contain the three points. If the thre points are in a line, means that we can find only two of these parameters.
[tex]P1: 7= 6a+9b+c\\P2: 0= 9a+6b+c\\P3: -6= 12a-5b +c[/tex]
Since you can determine a, b and c ( I ended up with [tex]a=-\frac {10}3; b=-\frac18; c= \frac{123}8[/tex] but I probably messed something in there) the thre points are not in a line
help me with math and ill mark brainliest
Answer:
I and II
Step-by-step explanation:
All trapezoids have a midsegment. The base angles of isosceles trapezoids are always congruent. Because the top and bottom side are parallel, the same side interior angles are supplementary not complementary.
dear and kind community I have a question that urges me which is the following, let's imagine that there are 73 million coins that can be fractioned to a hexadecimal value of a minimum unit of 0.00000001 and would need 0.99999998 to reach a full unit of the coin 1, my question is what would happen if instead of this minimum hexadecimal number of coin 0.00000001 was a hundred 100=1? how many coins would exist if before it was 73 million with hexadecimals (0,00000001) now with a hundred it would be equivalent to one unit (1=100) how many coin units would there be? if now each unit would only be divided in hundreds and not in hexadecimals? thanks in advance to the one who responds.
Answer:
that have no answer so sorry
If point A is located at (-7 , 5) on a coordinate plane, and point B is located at (4 , 5), what is the distance between the two points?
Answer:
[tex]11[/tex]
Step-by-step explanation:
[tex]\sf{Use\: the\: distance\: formula\: to\: determine\: the\: distance\: between\: two\: points.[/tex]
[tex]\sf{Distance=\sqrt{(x_2 - x_1)^2 + (y_2-y_1)^2}[/tex]
[tex]\mathrm{Plug\:the\:points}[/tex]
[tex]\sqrt{\left(4-\left(-7\right)\right)^2+\left(5-5\right)^2}[/tex]
[tex](4+7)^2=11^2\\(5-5)^2=0[/tex]
[tex]\sqrt{11^2+0}[/tex]
[tex]11^2+0=11^2\\\sqrt{11^2}[/tex]
[tex]\mathrm{Apply\:radical\:rule:\:}\sqrt[n]{a^n}=a,\:\quad \mathrm{\:assuming\:}a\:\mathrm{is\ greater\ than \:or\ equal\: to \:0}[/tex]
[tex]=11[/tex]
the difference between factors and factor pairs
Answer:
Factors are often given as pairs of numbers, which multiply together to give the original number. These are called factor pairs. A square number will have one factor pair consisting of one factor multiplied by itself. This factor is called the square root of the given number.
(d). Find the area of the region enclosed by the graphs of f(x)= x³ and g(x)=x²+2x. [Verify your answer by MATHEMATICA and attach the printout of the commands and output (e). Find the area of the region enclosed by the graphs of y = 3/X and y=4-X. [Verify your answer by MATHEMATICA and attach the printout of the commands and output
Answer:
d . 37/12 unit^2.
Step-by-step explanation:
d) First find the points of intersection of the the 2 graphs, by solving them simultaneously:
x^3 = x^2 + 2x
x^3 - x^2 - 2x) = 0
x(x^2 - x - 2) = 0
x(x - 2)(x + 1) = 0
So they intersect at x = -1, x = 0 and x = 2.
Take the area from x = 0 to x = 2)
2 2
Area = ∫ x^2 + 2x dx - ∫ x^3 dx
0 0
2
= [ x^3/3 + x^2 ) - x^4/4]
0
= ((8/3 + 4) - 0) - (16/4 - 0) -
= 8/3 unit^2
Now calculate the area from x = -1 to x = 0.
0
= (x^3/3 + x^2 ) - x^4/4 )
-1
= (( 0 +1/3 - 1) ) - (0 - 1/4)
= 5/12 unit^2
So the total area of the region = 8/3 + 5/12 = 37/12 unit^2.
BETWEEN WHAT TWO INTEGERS IS THE FIRST ZERO?
Answer:
0 and 1
Step-by-step explanation:
The scale of the graph is not marked, so we assume each grid line represents 1 unit. The leftmost crossing of the x-axis is between 0 and 1.
_____
Additional comment
The other real zero is between 2 and 3. If this is a polynomial function, it will have additional complex zeros.
3. (a) Find the greatest common divisor of 34 and 89 using the Euclidean algo rithm.
(b) Express gcd (34, 89) as a linear combination of 34 and 89.
(c) Find an inverse of 34 modulo 89.
(d) Solve the linear congruence 34x = 53(mod 89).
a. We have GCD(34, 89) = 1; using the Euclidean algorithm,
89 = 2•34 + 21
34 = 1•21 + 13
21 = 1•13 + 8
13 = 1•8 + 5
8 = 1•5 + 3
5 = 1•3 + 2
3 = 1•2 + 1
b. Working backwards,
1 = 3 - 2
1 = 3 - (5 - 3) = 2•3 - 5
1 = 2•(8 - 5) - 5 = 2•8 - 3•5
1 = 2•8 - 3•(13 - 8) = 5•8 - 3•13
1 = 5•(21 - 13) - 3•13 = 5•21 - 8•13
1 = 5•21 - 8•(34 - 21) = 13•21 - 8•34
1 = 13•(89 - 2•34) - 8•34 = 13•89 - 34•34
c. Using the linear combination find in part b,
1 ≡ 13•89 - 34•34 (mod 89)
1 ≡ (-34)•34 (mod 89)
and
-34 ≡ -34 + 89 ≡ 55 (mod 89)
So, the inverse of 34 modulo 89 is 55.
d. Multiply both sides of the congruence by the inverse of 34:
55•34x ≡ 55•53 (mod 89)
x ≡ 2915 ≡ 32•89 + 67 ≡ 67 (mod 89)
Today only, a table is being sold at a 33% discount. The sale price is 201.
What was the price yesterday?
A driver travels 120 miles, stops, and then travels ¼ of the distance she has already driven. After stopping again, the driver travels ⅔ of the distance she has already traveled. Now, the entire distance she has driven is 55 miles more than 1 ⅔ of the remaining trip. How many miles does the driver still have to travel?
Answer:
75 miles
Step-by-step explanation:
We know that she has driven 120 miles before the first stop.
Then she drives for 1/4 of the the distance she has already driven (120 miles). One fourth of 120 is 30.
So now, she's driven for 120 + 30 miles, or 150 miles.
She drives for another 2/3 of the distance she's traveled (150 miles). Two thirds of 150 is 100.
So now, she's driven for 150 + 100 miles, or 250 miles.
What we need to find out now is how much of the trip has she traveled.
We know that the entire distance she has driven is 55 miles more than 1 ⅔ of the remaining trip. So, in other words, the distance she has traveled minus 55 is equal to 1 2/3 of the trip.
To put this in an equation:
250 - 55 = 1 2/3t
t = the whole trip
Now, we solve for t.
250 - 55 = 195
1 2/3 = 5/3
so, 195 = 5/3t
t = 325
We subtract what she has already driven to the total to get the remaining distance.
325 - 250 = 75
Find (a) the axis of symmetry and (b) the vertex of the graph of the function.
Ax) = 4x² - 8x
Step-by-step explanation:
I am not sure, what is the level of math for you currently.
do you do differentiation and derivatives already ?
because that is how I find "extreme points" and "turning points" of a function right away.
the vertex is the turning point for a quadratic parabola.
that means the point where the slope (= the first derivative) of the function is 0.
and that is also where the axis of symmetry is.
8x - 8 = 0
8x = 8
x = 1 (axis of symmetry).
y = 4×1² - 8×1 = 4 - 8 = -4
so, the vertex is (1, -4)
in case you don't understand derivatives yet, there is a shortcut for this for quadratic equations (fyi - in fact, the generic result of the first derivative) :
y = ax² + bx + c
the x value for the axis is then
x = -b/(2a)
in our case
a = 4
b = -8
x = - -8/8 = 8/8 = 1
and then y is calculated as above.
what is the value of x
Answer:X= 41
Step-by-step explanation:
Determine the greatest common factor of the numbers 24 and 56
Answer:
8
Step-by-step explanation:
yw :)
Solve the following system of equations:y=x2−4x+3 y=2x−2
[tex]y = 2x -2 ~~~~.....(i) \\\\y = x^2 -4 x +3 ~~~~ .....(ii) \\\\\\x^2-4x +3 = 2x -2\\\\\implies x^2 -4x -2x +3 +2 =0\\\\\implies x^2 -6x +5 =0\\\\\implies x^2 -5x -x +5 =0\\\\\implies x(x-5) -(x-5) =0\\\\\implies(x-5)(x-1) =0\\\\\implies x = 5 ~~ \text{or}~~ x = 1 \\\\\\\text{Substitute x = 1 in equation (i):}\\\\y = 2 -2 =0\\\\ \text{Substitute x = 5 in equation (i):}\\\\\\y = 2(5) -2 = 10 -2 =8 \\\\\text{Hence,}~~ (x,y) = (1,0) ~ \text{and} ~ (x,y) = (5,8)[/tex]
I need help... pls.
Answer:
Administer 14 ml, 350mg/125mg=2.8×5ml=14ml
whats the answers can anyone answer this question please
Answer:
1. B
2. A
Step-by-step explanation:
1.
10^{-2} means that you move the decimal back two times
B is the only option that represents that correctly.
2.
5 * 10^{4} = 50000
2.5 * 10^{2} = 250
50000/250 = 200
Out of the options, A is the only option in which the equation also equals 200.
How much is 2+10.
Please help me i dont know
Will give brainliest
Answer: 12
2 + 10
12
:)
Answer: 12
Step-by-step explanation: just add 2 to 10
Michelle is scuba diving. Her position changes from -2.1 m to -38.6 m in 6 1/4 minutes. What is the average change in Michelle’s position each minute. Show your work.
Answer: 5.824 m / min
Step-by-step explanation:
Change in position = -2.1m to -38.6m
Distance = |-38.6 m - (-2.1m) |
=|-36.5| m
= 36.5 m
Time =
The average change in Michelle's position each minute =
Hence, the average change in Michelle's position each minute = 5.824 m / min
Find an equation of the line drawn below.
Answer:
y = -2x +4
Step by step explanation:
y = -2x +4
Hello, hope you are having a splendid day.
First, we should calculate the slope of the line (Rise/Run)
The rise is how many units we move up or down; the run is how many units we move left or right.
Here, we move down 2 and over 1, so the slope is -2
Now, the y-intercept is where the graph touches the y-axis.
Here, the y-intercept is 4.
Our equation looks lke so:
y=-2x+4
Hope it helps. Ask me if you have any queries.
~An emotional teen who helps others on Brainly :)
[tex]MagicalNature[/tex]
Good luck.
Which of the functions represents a function?
Answer:
B.
Step-by-step explanation:
im not sure to my answer(●'◡'●)
How is solving for speed similar to solving for time
Answer: The both involve writing a rate
I hope this helps i would appreciate brainliest if possible :)
For the amusement of the guests, some hotels have elevators on the outside of the building. One such hotel is 400 feet high. You are standing by a window 100 feet above the ground and 150 feet away from the hotel, and the elevator descends at a constant speed of 20 ft/sec, starting at time t = 0, where t is time in seconds. Let θ be the angle between the line of your horizon and your line of sight to the elevator. 4 (a) Find a formula for h(t), the elevator's height above the ground as it descends from the top of the hotel. h(t) = (b) Using your answer to part (a), express θ as a function of time t. θ(t) = Find the rate of change of θ with respect to t. dθ dt = (c) The rate of change of θ is a measure of how fast the elevator appears to you to be moving. At what time does the elevator appear to be moving fastest? time = seconds At what height does the elevator appear to be moving fastest?
9514 1404 393
Answer:
a. h(t) = -20t +400
b. θ(t) = arctan(2 -2/15t); dθ/dt = -30/(1125 -120t +4t^2)
c. 15 seconds; 100 ft
Step-by-step explanation:
a. The initial height of the elevator is 400 ft. The rate of change of height is -20 ft/s, so the height equation can be ...
h(t) = -20t +400
__
b. The tangent of the angle above the line of sight is "opposite"/"adjacent":
tan(θ) = (h(t) -100)/(150) = -2/15t +2
θ(t) = arctan(2 -2/15t) . . . . radians
The derivative of the angle function is ...
dθ/dt = 1/(1+(2 -2/15t)^2)(-2/15)
dθ/dt = -30/(1125 -120t +4t^2)
__
c. The value of dθ/dt will have a peak where the denominator has a minimum, at t = -(-120)/2(4)) = 15. (The quadratic vertex coordinate is t=-b/(2a).)
The elevator appears to be moving fastest at t=15 seconds.
The height at that time is ...
h(15) = 400 -20(15) = 100
The elevator appears to be moving fastest when it is at eye level, 100 ft above the ground.
PLEASE HELP WITH THIS ONE QUESTION
Answer:
The graph moved down 5 units
Step-by-step explanation:
Answer:
Step-by-step explanation:
The best way to get an answer to this question is to study the graph you get when you study the result from Desmos, which is a free graphing program.
Notice the way the graph is laid out. If the graph was simply y = x^2 - 6x then the y value for the minimum value would be x = 3 (just like the 2 values you do get) and y = -9
But y = x^2 - 6x + 3 has you moving up 3 units to y = - 6 and y = x^2 - 6x + 8 moves you to y = - 1. Which way are you going? The difference is 5 units and you are moving down because you start at y = x^2 - 6x + 8 and move down to x^2 - 6x + 3.
Without finding minimums (which is a cumbersome process which needs to be done twice) there's no easy way to do this except graphing.
The answer is B.
Find the slope of the line that passes through:
(-3,-4) and (76)
Answer:
Point slope form: y − 7 = 3 4 ( x − 3 ) Slope intercept form: y = 3 4 x + 19 4 or y = 3 4 x + 4 3 4
Step-by-step explanation:
hope this helps, have a nice day/night! :D
if it helped, please mark this as brainliest!
Answer:
Slope = 1
Step-by-step explanation:
Slope = change in y / change in x
Slope = 6 - (-4)/7 - (-3)
Slope = 10/10
Slope = 1
-Chetan K
positive and negative relationships are both examples of linear relationships
A. True
B false
Answer: A. True.
Step-by-step explanation:
A relationship is linear when the points on a scatterplot follow a somewhat straight line pattern. This is the relationship that we will examine. Linear relationships can be either positive or negative. Positive relationships have points that incline upwards to the right. As x values increase, y values increase.