Answer :
To evaluate the function
[tex]$$
f(x) = -5x^2 - x + 20
$$[/tex]
at [tex]$x = 3$[/tex], follow these steps:
1. Substitute [tex]$x = 3$[/tex]:
[tex]$$ f(3) = -5(3)^2 - 3 + 20. $$[/tex]
2. Calculate the square:
[tex]$$ 3^2 = 9. $$[/tex]
3. Multiply by [tex]$-5$[/tex]:
[tex]$$ -5(9) = -45. $$[/tex]
4. Combine the other terms:
The function now becomes
[tex]$$ f(3) = -45 - 3 + 20. $$[/tex]
5. Add the terms sequentially:
First, add [tex]$-45$[/tex] and [tex]$-3$[/tex]:
[tex]$$ -45 - 3 = -48. $$[/tex]
Then add [tex]$20$[/tex]:
[tex]$$ -48 + 20 = -28. $$[/tex]
Thus, the value of [tex]$f(3)$[/tex] is
[tex]$$
\boxed{-28}.
$$[/tex]
[tex]$$
f(x) = -5x^2 - x + 20
$$[/tex]
at [tex]$x = 3$[/tex], follow these steps:
1. Substitute [tex]$x = 3$[/tex]:
[tex]$$ f(3) = -5(3)^2 - 3 + 20. $$[/tex]
2. Calculate the square:
[tex]$$ 3^2 = 9. $$[/tex]
3. Multiply by [tex]$-5$[/tex]:
[tex]$$ -5(9) = -45. $$[/tex]
4. Combine the other terms:
The function now becomes
[tex]$$ f(3) = -45 - 3 + 20. $$[/tex]
5. Add the terms sequentially:
First, add [tex]$-45$[/tex] and [tex]$-3$[/tex]:
[tex]$$ -45 - 3 = -48. $$[/tex]
Then add [tex]$20$[/tex]:
[tex]$$ -48 + 20 = -28. $$[/tex]
Thus, the value of [tex]$f(3)$[/tex] is
[tex]$$
\boxed{-28}.
$$[/tex]