If a(x+2)+b(x+2)=60 and a+b=12, then x is equal to
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Solution
The equation $a(x+2) + b(x+2) = 60hasacommonfactorofx+2$ on the left side.
Thus, we can re-write the equation as (a+b)(x+2)=60.
When a+b=12, we obtain 12⋅(x+2)=60 and so x+2=5 which gives x=3.
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