Question

determine o valor de x no feixe de retas a seguir.

Answer 1

4x/4x+20 =  4x-8/4x+8
16x²+32x=16x² -32x+80x-160
16x=160
x=10

Answer 2

4x+8/4x-8=4x+20/4x
4*(4x+8) = (4x-8)*(4x+20)
16x^2+32x=16x^2+80x-32x-160
16x^2-16x^2+32x+32x-8x=-160
-16x=-160
x=10