Question

How do you solve `x^2−8x+16=0` using the quadratic formula?

Answer 1

`x=4`

Explanation:

The quadratic formula is defined by:
`x=(-b((+/-)sqrt(b^2-4ac)))/(2a)`
where `a` is the coefficient in front of `x^2`, `b` is the coefficient in front of `x`, and c is the last coefficient.

Plugging in 1 for a, -8 for b, and 16 for c:

`x=(8((+/-)sqrt(64-4(1)(16))))/(2(1))`

Simplify:

`x=(8((+/-)sqrt(0)))/(2(1))`

`sqrt0=0` and the positive and negative of 0 is just 0. So it becomes:

`x=8/2=4`