Question

If 9 (x) = – 5x2 – 4x + 19 find f (–3)

Answer 1

Answer:

- 14

Step-by-step explanation:

$f(x) = - 5 {x}^{2} - 4x + 19 \\ plug \: x = - 3 \\ f( - 3) = - 5 {( - 3)}^{2} - 4( - 3) + 19 \\ f( - 3) = - 5 \times 9 + 12 + 19 \\ f( - 3) = - 45 + 31 \\ f( - 3) = -14$