help please. oh i need it

Answer:

(a) When a = 4 and b = -5,  a² + b² - a·b = 61

(b) When a = 4 and b = -5,  a³·b + a·b² = -220

(c)  [tex]When \ a = 4 \ and \ b = -5, \ \dfrac{a - b}{a + b} + a -b = 0[/tex]

(d) When a = 4 and b = -5, (a + b)² - (a - b)² = 82

Step-by-step explanation:

The question relates to evaluation of expressions, given the values of the variables, "a" and "b"

Where;

a = 4 and b = -5

(a) For a² + b² - a·b, we have;

a² + b² - a·b = 4² + (-5)² - 4 × (-5) = 16 + 25 + 20 = 41 + 20 = 61

(b) For a³·b + a·b² we have;

a³·b + a·b² = 4³·(-5) + 4·(-5)² = 64 × (-5) + 4 × 25 = -320 + 100 = -220

(c) For [tex]\dfrac{a - b}{a + b} + a -b[/tex], we have;

[tex]\dfrac{a - b}{a + b} + a -b = \dfrac{4 - (-5)}{4 + (-5)} + 4 - (-5) = \dfrac{4 + 5}{4 -5} + 4 + 5= \dfrac{9}{-1} + 4 + 5 = -9 + 4 + 5 = 0[/tex]

[tex]\therefore when \ a = 4 \ and \ b = -5, \ \dfrac{a - b}{a + b} + a -b = 0[/tex]

(d) For (a + b)² - (a - b)² we have;

(a + b)² - (a - b)² = (4 + (-5))² - (4 - (-5))² = (4 - 5)² - (4 + 5)² = (-1)² - 9² = 1 + 81 = 82

When a = 4 and b = -5, (a + b)² - (a - b)² = 82

Answer:

Answer

Step-by-step explanation:

I believe it is the first or second choice. I believe it is the first choice, but it could be the second one.

Sorry hope it helps.

Answer:

15/16

Step-by-step explanation:

5×3=15

4×4=16

if they're two - you count them +

(my English is not very good :( )

Answer:

16

if you are happy with my answer, please give brainliest :)

Step-by-step explanation:

Plug in:

8+8

Answer:

16

Step-by-step explanation:

2 × 4 = 8

8+8= 16

your answer is 16 when x equals 4

Answer:

new York cheese cake $5

Apple cheese cake $10

Answer:

45x + 180 = 900

x being number of weeks

Step-by-step explanation:

The equation that can be used to find the number of weeks is 180+45x = 900 and the number of weeks she must save the money is 16 weeks.

It is defined as the relation between two variables if we plot the graph of the linear equation we will get a straight line.

If in the linear equation one variable is present then the equation is known as the linear equation in one variable.

We have:

The amount of money Jenny saved each week = $45

The amount her brother gives = $180

Total amount Jenny wants to save = $900

Let's suppose the number of weeks is x

180+45x = 900    (as she has already $180 and each week she saves is                                    

                              $45)                

So from the above equation, we can find the number of weeks.

After solving the equation:

45x = 900 - 180

x = 16 weeks

Thus, the equation that can be used to find the number of weeks is 180+45x = 900 and the number of weeks she must save the money is 16 weeks.

Learn more about the linear equation here:

brainly.com/question/11897796

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Answer:

B

Step-by-step explanation:

Answer:

Given that you're providing only a single term, asking for a difference doesn't make a lot of sense.  I assume you're asking to have the expression simplified?

If so, then it can be reduced to (x - 17) / 3x

Step-by-step explanation:

You can simplify by multiplying both terms each by a different ratio that equals one, but also gives the terms common denominator.  Multiplying the first one by x²/x² and the second by 3x/3x will do that for you.

After that you can group the terms into one fraction and simplify:

[tex]\frac{x - 8}{3x} - \frac{3x}{x^2} \\\\= \frac{x - 8}{3x}\times\frac{x^2}{x^2} - \frac{3x}{x^2} \times\frac{3x}{3x} \\\\= \frac{x^3 - 8x^2}{3x^3} - \frac{9x^2}{3x^3} \\\\= \frac{x^3 - 8x^2 - 9x^2}{3x^3} \\\\= \frac{x - 8 - 9}{3x}\\\\= \frac{x - 17}{3x}\\[/tex]

Answer:

The difference of [tex]\frac{x-8}{3x}-\frac{3x}{x^2}[/tex]  is [tex]\mathbf{\frac{x-17}{3x}}[/tex]

Step-by-step explanation:

We need to find the difference: [tex]\frac{x-8}{3x}-\frac{3x}{x^2}[/tex]

Simplifying to find the difference:

[tex]\frac{x-8}{3x}-\frac{3x}{x^2}[/tex]

x is common in both 3x and x^2 so, we can cancel it out and we get:

[tex]=\frac{x-8}{3x}-\frac{3x}{x(x)}\\=\frac{x-8}{3x}-\frac{3}{x}[/tex]

Now, taking LCM of 3x and x we get 3x, We will multiply 3x with both terms and then solve we get:

[tex]=\frac{x-8-3(3)}{3x}\\=\frac{x-8-9}{3x}\\=\frac{x-17}{3x}[/tex]

It cannot be further simplified, so we get [tex]\frac{x-17}{3x}[/tex] as answer.

So, The difference of [tex]\frac{x-8}{3x}-\frac{3x}{x^2}[/tex]  is [tex]\mathbf{\frac{x-17}{3x}}[/tex]

Answer:

34 and 17

Step-by-step explanation:

x+y=51

2y=x

2y+y=51

3y=51

y=17

2(17)=x

x=34

9514 1404 393

Answer:

  f(-2) = -12

Step-by-step explanation:

Put -2 where x is and do the arithmetic.

  [tex]f(x)=-3x^2\\\\f(-2)=-3(-2)^2=-3\cdot4=\boxed{-12}[/tex]

Answer: 13x - 14

Step-by-step explanation:

3x + 10x - 14

13x -14

Answer:

13x-14

Step-by-step explanation:

Answer:

30seconds

Step-by-step explanation:

if it takes 2 seconds to walk 3steps then in 30 seconds she should have walked 60 steps.

Answer: I got -1, I honest don’t know if i was doing it right so here is my explanation

Step-by-step explanation:

I distributed 2(4x-5)

5x+3x=20x-10-2

Sub 3x for 20x

5x=17x-10-2

Sub -10-2

5x=17x-12

Sub 5x-17x

12x=-12

Divide

Equals -1

Sry it took me a bite

Answer:

d) the line crosses the y-axis above the origin

Step-by-step explanation:

your welcome

Answer:

y= 1/2 x +7

the slope is 1/2 since hwne it's perpendicular, it's reciprocal and the sign also changes

Step-by-step explanation:

3= -4 +b

b= 7

Answer:

2-

Step-by-step explanation:

[tex]x = 10 \\ 3(10) + 5y = 20 \\ 30 + 5y = 20 \\ 5y = - 10 \\ y = - 2[/tex]

Answer: i think the answer is b

Step-by-step explanation:

think u

Answer:

Add the table and i might answer correctly

Step-by-step explanation:

Answer:

40! Seconds

Step-by-step explanation:

Calculation for After how many seconds will the two fish tanks have the same amount of water

First step

Based on the information given let the equation be :

150-1/2x=120+1/4x

Second step

Now let solve for x which means that x will be the number of second by multiplying both side by 4

4(150-1/2x)=4(120+1/4x)

=600-2x=480+x

Third step

Let Add 2x on both side

600=480+3x

Third step

Let Subtract 480 on both side

600-480=480-480+3x

120=3x

Last step is to divide both side by 3

120/3=3x/3

40=x

Hence:

x=40 seconds

Therefore After 40 seconds the two fish tanks will have the same amount of water.

Answer:

Any 2 circles in the plane are similar.

Step-by-step explanation:

No, I disagree.

Any 2 circles in the plane are congruent only when their diameters have equal length.

Any 2 circles in the plane are similar.

The likely error in Manuel's claim is 552.61 in².

We have,

Height = 16 in

Diameter = 11 in

radius = 5.5 in

The surface area of a cylinder.

= 2πrh + 2πr²

= 2 x 3.14 x 5.5 x 16 + 2 x 3.14 x 5.5²

= 552.64 + 189.97

= 742.61 in²

Now,

Manuel incorrectly claimed that the surface area of the cylinder is

190.0 in²

Error = Correct surface area - Claimed surface area

Error = 742.61 in² - 190.0 in²

Error ≈ 552.61 in²

Thus,

The likely error in Manuel's claim is 552.61 in².

Learn more about cylinder here:

https://brainly.com/question/15891031

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Answer:

90 degrees

Step-by-step explanation:

Assuming that this polygon is a square, x would be 90 degrees. In a square, all angles are right angles.

Answer:

the thrid one

Step-by-step explanation:

Answer:

Options A, B, C and D

Step-by-step explanation:

This question is not complete; here is the complete question.

Tori bought 24 candy bars for 69 cents each. She used partial products to find the total cost in cents. Which are NOT possible partial products for 24 × 69?

A. 24

B. 36

C. 180

D. 240

E. 1656

Cost of one candy = 69 cents  

Since, cost of 24 candies = Cost of one candy × Number of candies

                                          = 69 × 24

For partial product,

69 × 24 = (60 + 9)(20 + 4)

             = 60(20 + 4) + 9(20 + 4)

             = 60×20 + 60×4 + 9×20 + 9×4

             = 1200 + 240 + 180 + 36

             = 1656

Therefore, Options A, B, C and D are not possible partial products.

Answer:

3 kilograms

Step-by-step explanation:

one is for liquids and the others are too small i think

Answer:

6 cm

Step-by-step explanation: