Answer:
Yes
Step-by-step explanation:
f(x) = x³ − 9x² + 11x + 21
f(3) = (3)³ − 9(3)² + 11(3) + 21
f(3) = 27 − 81 + 33 + 21
f(3) = 0
cross multiply the equation to give you
1= a(2bh+3)
divide both sides by a(2b+3)
answer is 1/2ab+3 = h
You didn't ask a question but its called a period
800 + 16x = 720 + 21x. Cancel out the 720 to get 80 + 16x = 21x. Subtract 16x from both sides to get 80 = 5x. Divide by 5 to get 16 = x, or x = 16. 16 hours. The charge is 800 + 16(16), = 720 + 21(16) which = 800 + 256 = 720 + 336 which = 1,056 = 1,056. Hope this helped!
