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Suppose that a(x+b(x+3))=2(x+6) for all real values of x, find a+b. I have tried subsituting y for x+3 and solving that way but I could not find a solution. Could someone point me in the right direction? Thanks!

 Sep 25, 2022
 #1
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Its -4 👍😎

 Sep 25, 2022
edited by Supermantorr  Sep 25, 2022
edited by Supermantorr  Sep 25, 2022
 #2
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Simplify: 

 

\(a(x+b(x+3)) = 2(x+6)\)

\(a(x+bx+3b) = 2x + 12\)

\(ax+abx+3ab = 2x + 12\)

 

Equate coefficicents:

 

\(ab = 4\)

\(a + ab = 2\)

 

Solving this system, we find \(a = -2\) and \(b = -2\) so \(a + b = \color{brown}\boxed{-4}\)

 Sep 25, 2022
 #3
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Ohhhh, thank you so much I understand it now!

Guest Sep 25, 2022

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