We're gonna solve x squared plus
x minus 30 equals zero
using the quadratic formula.
So a will be one, b will be
one and c will be negative 30.
So putting those values into our formula,
we'll get negative one plus plus or minus
one squared minus four times
one times negative 30
over two times one.
When we simplify that,
we'll get negative one plus
or minus the square root of 121
over two.
And then that is equal
to negative one plus
or minus 11 over two.
So we'll have two possible answers.
X is either equal to negative
one plus 11 over two.
Or x is equal to negative
one minus 11 over two.
So negative one plus 11 over
two give us x equals five.
Or negative one minus 11 is negative 12.
Divided by two gives us negative six.
