Answer:
(8x+4) ( x-5)
Explanation:
Well we can't factor out the 8 and solve because if we do the -20 and -36 will be decimals.
So we do this
8 * -20 = -160
We need to find 2 number that multiplies to -160 and adds to -36
-40 and 4 fit this category
they add to -36 and multiply to -160
Now we write the equation as
8x^2 - 40x + 4x -20
(8x^2-40x) (4x-20)
8x(x-5) + 4(x-5)
(8x+4) ( x-5)