Question

For the function f(x)=−7x2+8x−8, find f(4).

Answer 1

Answer:

- 88

Step-by-step explanation:

$f(x ) = - 7 {x}^{2} + 8x - 8 \\ plug \: x = 4 \\ \\ \implies \: f(4 ) = - 7 {(4)}^{2} + 8(4) - 8 \\\\ \implies \: f(4 ) = - 7 \times 16 + 32 - 8 \\\\ \implies \: f(4 ) = - 112+ 32 - 8 \\ \\ \implies \: f(4 ) = - 120+ 32 \\\\ \implies \: f(4 ) = - 88$