Question

How do you solve `2x^2+7x-5=0` by completing the square?

Answer 1

`x = (-7 +- sqrt89)/4`

Explanation:

`2x^2 + 7x = 5`
`x^2 + (7x)/2 = 5/2`
`x^2 + (7x)/2 + 49/16 = 5/2 + 49/16`
`(x + 7/4)^2 = 89/16`
`x + 7/4 = +- sqrt89/4`
`x = - 7/4 +- sqrt89/4 = (- 7 +- sqrt89)/4`