Question

Please help with this, thankyouu

Answer 1

c = 3 and n = - 7

Explanation:

Expand the left side and compare the coefficients of like terms on both sides.

(5x + 4)(2x - c) ← expand using FOIL

= 10x² - 5cx + 8x - 4c ← factor out x from each of the terms in x

= 10x² + x( - 5c + 8) - 4c

Given this is equal to 10x² + nx - 12, then

Comparing the constant terms

- 4c = - 12 ( divide both sides by - 4 )

c = 3

Comparing the coefficients of the x- terms

n = - 5c + 8 = - 5(3) + 8 = - 15 + 8 = - 7

Thus

c = 3 and n = - 7

Answer 2

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Hi there!

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Let's solve for c.

`\left(5x\ +\ 4\right)\left(2x\ +\ c\right)\ =\ 10x^(2\ )+\ nx\ -\ 12`

Step 1: Add
`-10x^2` to both sides.

`5cx + 10x^2 + 4c + 8x + -10x^2 = nx + 10^2 - 12 + -10x^2`

`5cx + 4c + 8x = nx - 12`

Step 2: Add
`-8x` to both sides.

`5cx + 4c + 8x + -8x = nx - 12 + -8x`

`5cx + 4c = nx - 8x - 12`

Step 3: Factor out variable c.

`c(5x + 4) = nx - 8x - 12`

Step 4: Divide both sides by
`5x+4`.

`(c(5x +4))/(5x + 4) = (nx-8x-12)/(5x + 4)`

Answer :
`\boxed{(nx-8x-12)/(5x + 4) }`

❀Hope this helped you!❀

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