SOLUTION: If 2x(x+2)=30 and |x+7|=2. What is the value of x? Thanks for your help.

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Question 937556: If 2x(x+2)=30 and |x+7|=2. What is the value of x? Thanks for your help.
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
TWO equation in ONE unknown variable. Pick either equation and solve!

abs%28x%2B7%29=2
either -x-7=2, x%2B7=-2, highlight%28x=-9%29
OR
x%2B7=2, highlight%28x=-5%29.

Then, the other equation:
x%28x%2B2%29=15, after division by 2 on both sides.
x%5E2%2B2x-15=0
%28x-3%29%28x%2B5%29=0
highlight%28x=3%29 OR highlight%28x=-5%29

The value which satisfies BOTH equations is highlight%28highlight%28x=-5%29%29.