Question

Solve x2 – 8x = 20 by completing the square. Which is the solution set of the equation?

Answer 1

x= -2 and x=10

Explanation:

Answer 2

x=2 , x = 6

Explanation:

x² – 8x = 20 ⇌ x² – 2(4)x = 4 + 16 ⇌ x² – 2(4)x - 16 = 4 ⇌ (x - 4)² = 4

⇌ x - 4 = 2 or x - 4 = -2 ⇌ x = 6 or x = 2