Question

The first three steps of completing the square to solve the quadratic equation x^2 + 8x +5 = 0, are shown below.

Step 1: x^ + 8x= -5
Step 2: x^2 + 8x + 16 = -5 + 16
Step 3: (x + 4)^2 = 11

What are the next 3 steps?

Answer 1

4. Take the square root of each side

5. Subtract 4 from each side

6. Give the positive and negative answer

Explanation:

Step 1: x^ + 8x= -5

Step 2: x^2 + 8x + 16 = -5 + 16

Step 3: (x + 4)^2 = 11

Take the square root of each side: sqrt((x+4)^2) = ±sqrt(11)

x+4 = ±sqrt(11)

Subtract 4 from each side x+4-4 = -4 ±sqrt(11)

x = -4 ±sqrt(11)

List both answers x = -4+sqrt(11), x= -4-sqrt(11)

Answer 2

see explanation

Explanation:

step 4 take the square root of both sides

`√((x+4)^2)` = ±
`√(11)`

x + 4 = ±
`√(11)`

step 5 subtract 4 from both sides

x = - 4 ±
`√(11)`

step 6 solve for x

x = - 4 -
`√(11)` or x = - 4 +
`√(11)`