Question #c7dcd

1 Answer
Jan 20, 2018

x=6

Explanation:

Move the 80 over.
-(8-x)(10-x) = -8

FOIL or whatever you do,
-(80-18x+x^2) = -8

-1 to both sides
x^2-18x+80=8

Move the 8 over.
x^2-18x+72=0

Factor
(x-12)(x-6)=0

The answer is x=6 and 10
x=6 because 10 as x is unfeasible