it's easier to see what you have if you let
u = x+5
Then you have
5u^2+2u-7=0
(5u+7)(u-1) = 0
so, u = -7/5 or u=1
That means
x+5 = -7/5
x = -32/5
x+5 = 1
x = -4
(5(x+5)^2)+(2(x+5)^2)-7=0
1 answer
1 answer