Answer :
To find [tex]\( f(3) \)[/tex] for the function [tex]\( f(x) = -5x^2 - x + 20 \)[/tex], we'll substitute [tex]\( x = 3 \)[/tex] into the function and evaluate.
1. Start with 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 equation:
[tex]\( f(3) = -5 \times 9 - 3 + 20 \)[/tex]
5. Multiply [tex]\(-5\)[/tex] by [tex]\(9\)[/tex]:
[tex]\(-5 \times 9 = -45\)[/tex]
6. Substitute [tex]\(-45\)[/tex] into the equation:
[tex]\( f(3) = -45 - 3 + 20 \)[/tex]
7. Add and subtract the values:
[tex]\(-45 - 3 = -48\)[/tex]
[tex]\(-48 + 20 = -28\)[/tex]
So, [tex]\( f(3) = -28 \)[/tex].
1. Start with 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 equation:
[tex]\( f(3) = -5 \times 9 - 3 + 20 \)[/tex]
5. Multiply [tex]\(-5\)[/tex] by [tex]\(9\)[/tex]:
[tex]\(-5 \times 9 = -45\)[/tex]
6. Substitute [tex]\(-45\)[/tex] into the equation:
[tex]\( f(3) = -45 - 3 + 20 \)[/tex]
7. Add and subtract the values:
[tex]\(-45 - 3 = -48\)[/tex]
[tex]\(-48 + 20 = -28\)[/tex]
So, [tex]\( f(3) = -28 \)[/tex].
