Answer :
To find [tex]\( f(3) \)[/tex] for the function [tex]\( f(x) = -5x^2 - x + 20 \)[/tex], follow these steps:
1. Substitute 3 into the function: Replace every [tex]\( x \)[/tex] in the function with 3. So, the expression becomes:
[tex]\[
f(3) = -5(3)^2 - (3) + 20
\][/tex]
2. Calculate [tex]\( 3^2 \)[/tex]:
[tex]\[
3^2 = 9
\][/tex]
3. Multiply by -5:
[tex]\[
-5 \times 9 = -45
\][/tex]
4. Substitute and simplify further:
[tex]\[
f(3) = -45 - 3 + 20
\][/tex]
5. Perform the addition and subtraction in sequence:
- First, subtract 3 from -45:
[tex]\[
-45 - 3 = -48
\][/tex]
- Then, add 20 to -48:
[tex]\[
-48 + 20 = -28
\][/tex]
Therefore, the value of [tex]\( f(3) \)[/tex] is [tex]\(-28\)[/tex].
1. Substitute 3 into the function: Replace every [tex]\( x \)[/tex] in the function with 3. So, the expression becomes:
[tex]\[
f(3) = -5(3)^2 - (3) + 20
\][/tex]
2. Calculate [tex]\( 3^2 \)[/tex]:
[tex]\[
3^2 = 9
\][/tex]
3. Multiply by -5:
[tex]\[
-5 \times 9 = -45
\][/tex]
4. Substitute and simplify further:
[tex]\[
f(3) = -45 - 3 + 20
\][/tex]
5. Perform the addition and subtraction in sequence:
- First, subtract 3 from -45:
[tex]\[
-45 - 3 = -48
\][/tex]
- Then, add 20 to -48:
[tex]\[
-48 + 20 = -28
\][/tex]
Therefore, the value of [tex]\( f(3) \)[/tex] is [tex]\(-28\)[/tex].
