Question

What are the solutions of x2 + 20 = 12x.

Answer 1

x₁ = 2

x₂ = 10

Explanation:

x² + 20 = 12x

x² - 12x + 20 = 0

(x-2)(x-10) = 0

then:

x₁ = 2

x₂ = 10

Check:

x₁

2² + 20 = 12*2

3 + 20 = 24

x₂

10² + 20 = 12*10

100 + 20 = 120