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3 years ago

An equation and the first step in its solution are shown: Equation: x2 + 8x - 9 = 0

1 answer:

3 0

Answer- A-16

Because when doing completing the square, you divide the coefficient of x by 2, which is 4, and the square it which is 16

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What is the product of 2x -5 and 3x^2 + 5x - 7? Write your answer in standard form. A. Show your work. B. Is the product of 2x -

VikaD [51]

Answer:

A)What is the product of 2x -5 and 3x^2 + 5x - 7? Write your answer in standard form.

6x³ - 5x² - 39x + 35 = 0

B. Is the product of 2x -5 and 3x^2 + 5x -7 equal to the product of 5x - 2 and 3x^2 + 5x - 7?

No it is not.

Step-by-step explanation:

A)What is the product of 2x -5 and 3x^2 + 5x - 7? Write your answer in standard form.

(2x - 5) (3x² + 5x - 7)

= 2x(3x² + 5x - 7) -5(3x² + 5x - 7)

= 6x³ + 10x² - 14x -15x² - 25x +35

Collecting like terms

= 6x³ +10x² - 15x² - 14x - 25x +35

= 6x³ - 5x² - 39x + 35

In standard form

6x³ - 5x² - 39x + 35 = 0

B. Is the product of 2x -5 and 3x^2 + 5x -7 equal to the product of 5x - 2 and 3x^2 + 5x - 7?

First we find the product of

5x - 2 and 3x² + 5x - 7?

(5x - 2) (3x² + 5x - 7)

5x(3x² + 5x - 7) -2(3x² + 5x - 7)

15x³ + 25x² - 35x - 6x² -10x + 14

Collect like terms

15x³+ 25x² - 6x² -35x - 10x + 14

15x³ + 19x² - 45x + 14 = 0

Hence, the product of 5x - 2 and 3x^2 + 5x - 7

= 15x³ + 19x² - 45x + 14 = 0

The product of 2x -5 and 3x^2 + 5x -7 = 6x³ - 5x² - 39x + 35 = 0

Comparing both products, we can see that

The product of 2x -5 and 3x^2 + 5x -7 ≠ the product of 5x - 2 and 3x^2 + 5x - 7

6 0

3 years ago

I need help with #8. I need to use the quadratic formula. I have a calculator that is programmed for the quadratic formula so al

GuDViN [60]

Answer:

x = 14

Step-by-step explanation:

Extend line AB so that it intersects ray CE at point G. Then angles BGC and BAD are "alternate interior angles", hence congruent.

The angle at B is exterior to triangle BCG, and is equal to the sum of the interior angles at C and G:

138 = (376 -23x) +(x^2 -8x)

Subtracting 138 and collecting terms we have ...

x^2 -31x +238 = 0

For your calculator, a=1, b=-31, c=238.

<em>Additional comment</em>

You will find that the solutions to this are x = {14, 17}. You will also find that angle BCE will have corresponding values of 54° and -15°. That is, the solution x=17 is "extraneous." It is a solution to the equation, but not to the problem.

For x=14, the marked angles are A = 84°, C = 54°.

8 0

4 years ago

Peter also earns a certain amount per hour. The table shows the amount of money, in dollars, he earns in a given number of hours

drek231 [11]

To determine how much you get per hour, divide 44 by 4, 88 by 8, and 132 by 12. Each time you get 11, so you get 11 dollars an hour.

If y = money earned and x = number of hours worked, then

y=11x
because the money you get is 11 times the amount of hours you work.

Hope this helps and I can provide further explanation if needed!

3 0

3 years ago

(Please Help) Find the value of x.

nalin [4]

Answer:

x = 6.5.

Step-by-step explanation:

6(x + 6) = 15 * 5

6x + 36 = 75

6x = 39

x = 6.5.

7 0

4 years ago

2. I want to send out 25 Chitstmas cards so I will need 25 stamps. Each stamp cost $0.55; SO how much will I spend on stamps?

alexdok [17]

25 (stamps) x 0.55$ = 13.75$

8 0

3 years ago

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