Question

Solve x2 - 8x - 20 = 0.

x = 4, x = -5

x = -4, x = 5

x = 2, x = -10

x = -2, x = 10

Answer 1

look for two numbers the product is -20 and the sum is -8
try -10 and 2
(-10)(2)= -20 and -10+2=-8
x^2-8x-20=(x-10)(x+2), the roots are x=10 and x=-2

Answer 2

Thank you very much @lucaz !

Answer 3

welcome