Question

What is the answer to the equation x squared minus 2x equals 15.

Answer 1

Answer:

$x = 5 \\ x = - 3$

Step-by-step explanation:

${x}^{2} - 2x = 15 \\ {x}^{2} - 2x - 15 = 0 \\ {x}^{2} + 3x - 5x - 15 = 0 \\ x(x + 3) - 5(x + 3) = 0 \\ (x - 5)(x + 3) = 0 \\ x - 5 = 0 \: \: \: \: \: or \: \: \: \: x + 3 = 0 \\ x = 5 \: \: \: \: or \: \: \: \: \: \: x = - 3$