Question

The solution to 2x2 – 11 = 87 is .

Answer 1

x = 7, -7

Explanation:

2x² - 11 = 87

2x² = 98

x² = 49

x = +/-7

Answer 2

Explanation:

Step 1: Subtract 87 from both sides

`2x^2 - 11 - 87 = 87 - 87`

`2x^2 - 11 - 87 = 0`

Step 2: Factor

`2x^2 - 11 - 87 = 0`

`2(x + 7)(x - 7) = 0`

`x + 7 = 0` and
`x - 7 = 0`

`x = -7` and
`x = 7`

Answer:
`x = -7, 7`