please help with this, thankyouu

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Hi there!
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Let's solve for c.
[tex]\left(5x\ +\ 4\right)\left(2x\ +\ c\right)\ =\ 10x^{2\ }+\ nx\ -\ 12[/tex]
Step 1: Add [tex]-10x^2[/tex] to both sides.
[tex]5cx + 10x^2 + 4c + 8x + -10x^2 = nx + 10^2 - 12 + -10x^2[/tex]
[tex]5cx + 4c + 8x = nx - 12[/tex]
Step 2: Add [tex]-8x[/tex] to both sides.
[tex]5cx + 4c + 8x + -8x = nx - 12 + -8x[/tex]
[tex]5cx + 4c = nx - 8x - 12[/tex]
Step 3: Factor out variable c.
[tex]c(5x + 4) = nx - 8x - 12[/tex]
Step 4: Divide both sides by [tex]5x+4[/tex].
[tex]\frac{c(5x +4)}{5x + 4} = \frac{nx-8x-12}{5x + 4}[/tex]
Answer : [tex]\boxed{\frac{nx-8x-12}{5x + 4} }[/tex]
❀Hope this helped you!❀
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Answer:
c = 3 and n = - 7
Step-by-step 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