Given the function f(x)=-5x^2-x+20, find f(3)

Question

asked Feb 9, 2024 143k views

2 Answers

Bajrang Hudda · Answer 1 · 2024-02-10T12:06:57+0000

To find f(a) for any function, plug a into that function. Like so:

↔ f(x) = -5x² - x + 20

↔ f(3) = -5(3)^2 - 3 + 20

↔ f(3) = -5 * 9 - 3 + 20

↔ f(3) = -45 - 3 + 20

↔ f(3) = -48 + 20

↔ f(3) = -28

Greg Flynn · Answer 2 · 2024-02-14T20:34:17+0000

Answer:

f(3) = -28

Explanation:

Given the function:

$\sf f(x) = -5x^2 - x + 20$

To find f(3), we simply substitute 3 for x in the function. So, we have:

$\sf f(3) = -5 *( 3)^2- (3) + 20$

$\sf f(3) = -5 * 9 - 3 + 20$

$\sf f(3) = -45 - 3 + 20$

$\sf f(3) = -48 +20$

$\sf f(3) = -28$

Therefore, f(3) = -28.