Solve and check x^2 - x - 42 = 0

x^2 - x - 42 = 0

(x )(x ) ( -7)( +6)=0

(x-7) (x+6) = 0

Check:

(x-7) (x+6) = 0

(x)(x) (x)(6) (-7)(x) (-7)(6)

x^2 +6x -7x -42=0

x^2 -x -42=0

Solve:

(x-7)=0

x-7+7=0+7

x=7

Solve:

(x+6) = 0

x+6-6 = 0-6

x=-6