Question

Solve by completing the square. Show all work you use to arrive at your answer.
x² + 6x = 81

Answer 1

Answer:

x* = 81/6

x° = 13.5

so ok is thnms full for.you ok

Answer 2

Answer:

x = - 3 ± 3$\sqrt{10}$

Step-by-step explanation:

x² + 6x = 81

To complete the square

add ( half the coefficient of the x- term )² to both sides

x² + 2(3)x + 9 = 81 + 9

(x + 3)² = 90 ( take square root of both sides )

x + 3 = ± $\sqrt{90}$ = ± 3$\sqrt{10}$ ( subtract 3 from both sides )

x = - 3 ± 3$\sqrt{10}$ , then

x = - 3 - 3$\sqrt{10}$ , x = - 3 + 3$\sqrt{10}$