Question

X square + X - 20 equal to zero

Answer 1

x²+x-20=0
x²+(5-4)x-20=0
x²+5x-4x-20=0
x(x+5)-4(x+5)=0
(x-4)(x+5)=0

x=4 or x=-5

Answer 2

x² + x - 20 = 0
Here we can find the value of x by using the splitting method.
x² + 5x - 4x - 20 = 0
x(x + 5) - 4(x + 5) = 0
(x + 5) (x - 4) = 0
x = - 5 or x = 4

The value of x is - 5 or 4.

Hope this helps you.