I believe the answer is false
2. f(x) = x - 2x² - 5 + 10x
=-2x² + 8x - 5
f'(x)= -4x + 8
4. y = 100(45x - 30 - 3x³ + 2x²)
= 100(-3x³ + 2x² + 45x -30)
= -300x³ + 200x² + 4500x - 3000
y' = -900x² + 400x + 4500
90 minutes or 1 hour and 30 minutes.
Hope this helps,
kwrob
It is in the attachment.
Let me know if this helps.
also let me know if it shows up for you and if it don't ill post your answer in the comments.
7/9 = 42/54...when 42/54 reduces, it becomes 7/9...so this is proportional because proportions are nothing but equivalent fractions.
u could also check it this way...
12/21 = 15/24
cross multiply
(21)(15) = (12)(24)
315 = 288.....these do not equal and are therefore, not proportionate
440/4 = 300/3
110 = 100....not equal, so not proportionate
120/5 = 88/4
24 = 22.....not proportionate
66/82 = 99/123
0.804 = 0.804.......these are proportional
68/172 = 43/123
0.395 = 0.349......nope, not proportional