SOLUTION: 11. f(x) = 11x - 5x2 + 4 find f(-4) A. 619 B. -4,755 C. -6288203 D. 639 E. -120 F. -4595 12. f(x) = 7 - 5x + 7x2 find f(-9) A. 639 B. -4,755 C. -62882

Algebra ->  Functions -> SOLUTION: 11. f(x) = 11x - 5x2 + 4 find f(-4) A. 619 B. -4,755 C. -6288203 D. 639 E. -120 F. -4595 12. f(x) = 7 - 5x + 7x2 find f(-9) A. 639 B. -4,755 C. -62882      Log On


   

Question 1197780: 11. f(x) = 11x - 5x2 + 4
find f(-4)
A. 619
B. -4,755
C. -6288203
D. 639
E. -120
F. -4595

12. f(x) = 7 - 5x + 7x2
find f(-9)
A. 639
B. -4,755
C. -6288203
D. 619
E. -4595
F. 538
Found 2 solutions by josgarithmetic, math_tutor2020:
Answer by josgarithmetic(39618) About Me  (Show Source):
You can put this solution on YOUR website!
How do you need help on these two? Simple substitution.

Answer by math_tutor2020(3817) About Me  (Show Source):
You can put this solution on YOUR website!

I'll do problem 11 to get you started.

Replace every copy of x with -4. Then use PEMDAS to simplify.

f(x) = 11x - 5x^2 + 4
f(-4) = 11(-4) - 5(-4)^2 + 4
f(-4) = 11(-4) - 5(16) + 4
f(-4) = -44 - 80 + 4
f(-4) = -124 + 4
f(-4) = -120

Answer: -120