Solve: x^2+4x−5=0

Answer 1

which factor of 5 differ by 4?
One will be positive, the other negative.

Answer 2

x^2+4x-5 = 0. -5 = -1*5. -1+5 = 4 = B.
(x-1)(x+5) = 0
x-1 = 0, X = 1.
x+5 = 0, X = -5.