Question

How do you find the solution to the quadratic equation `- x^3 - x^2 + 21x + 45=0`?

Answer 1

Let's solve your equation step-by-step.

`−x^3−x^2+21x+45=0`

Step 1: Factor left side of equation.

`(−x−3)(x+3)(x−5)=0`

Step 2: Set factors equal to 0.

`−x−3=0 or x+3=0 or x−5=0`
`x=−3 or x=−3 or x=5`