Answer :
To find [tex]\( f(3) \)[/tex] for the function [tex]\( f(x) = -5x^2 - x + 20 \)[/tex], we need to substitute [tex]\( x = 3 \)[/tex] into the function and calculate the result step by step. Here's how you can do it:
1. Substitute [tex]\( x = 3 \)[/tex] into the function:
[tex]\( f(3) = -5(3)^2 - (3) + 20 \)[/tex]
2. Calculate [tex]\( 3^2 \)[/tex]:
[tex]\( 3^2 = 9 \)[/tex]
3. Multiply by [tex]\(-5\)[/tex]:
[tex]\(-5 \times 9 = -45 \)[/tex]
4. Substitute the values back into the expression:
[tex]\( f(3) = -45 - 3 + 20 \)[/tex]
5. Perform the addition and subtraction:
[tex]\(-45 - 3 = -48\)[/tex]
[tex]\(-48 + 20 = -28\)[/tex]
Therefore, [tex]\( f(3) = -28 \)[/tex].
1. Substitute [tex]\( x = 3 \)[/tex] into the function:
[tex]\( f(3) = -5(3)^2 - (3) + 20 \)[/tex]
2. Calculate [tex]\( 3^2 \)[/tex]:
[tex]\( 3^2 = 9 \)[/tex]
3. Multiply by [tex]\(-5\)[/tex]:
[tex]\(-5 \times 9 = -45 \)[/tex]
4. Substitute the values back into the expression:
[tex]\( f(3) = -45 - 3 + 20 \)[/tex]
5. Perform the addition and subtraction:
[tex]\(-45 - 3 = -48\)[/tex]
[tex]\(-48 + 20 = -28\)[/tex]
Therefore, [tex]\( f(3) = -28 \)[/tex].
