Answer :
To find [tex]\( f(3) \)[/tex] for the function [tex]\( f(x) = -5x^2 - x + 20 \)[/tex], we substitute [tex]\( x = 3 \)[/tex] into the function and simplify:
1. Start with the expression for the function:
[tex]\[
f(x) = -5x^2 - x + 20
\][/tex]
2. Substitute [tex]\( x = 3 \)[/tex] into the function:
[tex]\[
f(3) = -5(3)^2 - 3 + 20
\][/tex]
3. Calculate [tex]\( 3^2 \)[/tex]:
[tex]\[
3^2 = 9
\][/tex]
4. Substitute [tex]\( 9 \)[/tex] back into the expression:
[tex]\[
f(3) = -5 \times 9 - 3 + 20
\][/tex]
5. Calculate [tex]\( -5 \times 9 \)[/tex]:
[tex]\[
-5 \times 9 = -45
\][/tex]
6. Continue to simplify the expression:
[tex]\[
-45 - 3 + 20
\][/tex]
7. Calculate [tex]\( -45 - 3 \)[/tex]:
[tex]\[
-45 - 3 = -48
\][/tex]
8. Finally, add 20 to [tex]\(-48\)[/tex]:
[tex]\[
-48 + 20 = -28
\][/tex]
Therefore, the value of [tex]\( f(3) \)[/tex] is [tex]\(-28\)[/tex].
1. Start with the expression for the function:
[tex]\[
f(x) = -5x^2 - x + 20
\][/tex]
2. Substitute [tex]\( x = 3 \)[/tex] into the function:
[tex]\[
f(3) = -5(3)^2 - 3 + 20
\][/tex]
3. Calculate [tex]\( 3^2 \)[/tex]:
[tex]\[
3^2 = 9
\][/tex]
4. Substitute [tex]\( 9 \)[/tex] back into the expression:
[tex]\[
f(3) = -5 \times 9 - 3 + 20
\][/tex]
5. Calculate [tex]\( -5 \times 9 \)[/tex]:
[tex]\[
-5 \times 9 = -45
\][/tex]
6. Continue to simplify the expression:
[tex]\[
-45 - 3 + 20
\][/tex]
7. Calculate [tex]\( -45 - 3 \)[/tex]:
[tex]\[
-45 - 3 = -48
\][/tex]
8. Finally, add 20 to [tex]\(-48\)[/tex]:
[tex]\[
-48 + 20 = -28
\][/tex]
Therefore, the value of [tex]\( f(3) \)[/tex] is [tex]\(-28\)[/tex].
