Question

How do you solve using the quadratic formula `2x^2-6=-x`?

Answer 1

x =3/2 or -2

Explanation:

Rearrange to `x^2+x-6=0`
This does factorise to `(2x-3)(x +2)=0`
Giving x =3/2 or -2

The formula for solving the quadratic `ax^2+bx+c=0` is

`x=(-b+-sqrt(b^2-4ac))/(2a)`

Therefore `x=(-1+-sqrt(1-(4*2*-6)))/(2*2)`

`x=(-1+-sqrt(1+48))/4`

`x=(-1+7)/4 or (-1-7)/4`
`x=-6/4=-3/2 or x=-8/4=-2`