Question

The roots of a quadratic equation are 4 and -5. Which quadratic equation has these roots?

Answer 1

Answer:

(x-4)(x+5) or x^2+x-20

Step-by-step explanation:

If a root of the function is 4, (meaning that when y=0, x=4) it can be rewritten as x-4.

The same goes for if a root is -5. it will simplify to x+5.

These are called factors of a quadratic equation.

Put together, they look like (x-4)(x+5). Using the FOIL method, that can be simplified to x^2+x-20