Question

Re-write the quadratic function below in Standard Form
y = -9(x - 1)(x + 2)

Answer 1

y = - 9x² - 9x + 18

Explanation:

y = - 9(x - 1)(x + 2) ← expand factors using FOIL

= - 9(x² + x - 2) ← distribute parenthesis by - 9

y = - 9x² - 9x + 18 ← in standard form

Answer 2

-9x^2 - 9x + 18

Explanation:

-9 • (x - 1) • (x + 2)

-9x + 9 • (x + 2)

-9x^2 -18x + 9x + 18

-9x^2 - 9x + 18