Solve the equation by completing the square. Round to the nearest tenth.

Question

x^2 + 8x = 10
A. 1.1, 9.1
B. 1.1, -9.1
C. -1.1, 9.1
D. -1.1, -9.1

Answer 1

To complete the square for the equation x^2 + 8x = 10, we need to add and subtract (b/2)^2 to both sides of the equation.

In this case, b = 8 so (b/2)^2 = (8/2)^2 = 16.

x^2 + 8x + 16 = 10 + 16
(x + 4)^2 = 26

Now take the square root of both sides to solve for x:

x + 4 = ±√26
x = -4 ± √26

Rounded to the nearest tenth, this gives x ≈ -1.1, 9.1

So the answer is A. 1.1, 9.1