Question

Solve by factoring: x² - 15 = 2x ( rewrite it in standard form)

A) x² - 2x - 15 = 0
B) x² + 2x - 15 = 0
C) x² - 2x + 15 = 0
D) x² + 2x + 15 = 0

Answer 1

To solve the equation x² - 15 = 2x by factoring, rewrite it in standard form and factor the quadratic equation as (x - 5)(x + 3) = 0. The solutions are x = 5 and x = -3.

Step-by-step explanation:

To solve the equation x² - 15 = 2x by factoring, we first rewrite it in standard form:

x² - 2x - 15 = 0.

Now, we can factor the quadratic equation as (x - 5)(x + 3) = 0.

Setting each factor equal to zero, we have x - 5 = 0 or x + 3 = 0.

Solving for x, we find x = 5 or x = -3.

Therefore, the correct answer is A) x² - 2x - 15 = 0.