Question

How do you solve the equation `2x^2+8x+4=x^2+4x` by completing the square?

Answer 1

The equation has one root `x = -2`

Explanation:

First simplify the equation into a standard form
`2x^2+8x+4=x^2+4x`
becomes
`x^2 +4x+4 = 0` (equation 2)

Use the formula
`(-b+-sqrt(b^2-4ac))/(2a)`

substitute in the values from equation 2
`(-4+-sqrt(16-16))/2`

The equation has one root `x = -2`