Question

Solve x^2+8x+10=3 by completing the square

Answer 1

x = -1 and x = -7

Explanation:

Rewrite x^2+8x+10=3 as x^2 + 8x + 10=3

Now identify the coefficient of the x term.

It is 8. Halve that, getting 4, and then square

this result, getting 16.

Now add 16 and then subtract 16 in x^2 + 8x + + 10=3, as

follows: x^2 + 8x + 16 - 16 + 10=3

Simplify this in two ways: First, rewrite x^2 + 8x + 16 as (x + 4)^2, and

Combine -16 and 10: -6

and rewrite the equation as (x + 4)^2 - 6 = 3

Now add 6 to both sides: (x + 4)^2 = 9

Take the square root of both sides:

x + 4 = ±3

Then x = -4 + 3 and x = -4 -3, or x = -1 and x = -7

Answer 2

Use the formula

(b/2)^2

in order to create a new term. Solve for x

by using this term to complete the square.

x=−1,−7