Remember property of exponents
add exponents of same base
ok so
50,000 is 5 times 10^4
so
50000 times 10^15=
5 times 10^4 times 10^15=
5 times
=
5 times 10^19
We can factor this by using grouping. Take the leading coefficient and multiply it by the constant. In this case we get 5*-7 = -35.
Now we need 2 numbers that add to 2 and multiply to be -35. The numbers are -5 and 7.
So split the 2r into these two terms and group.
(5r^2 - 5r) + (7r - 7)
Factor both groups.
5r(r-1) + 7(r-1)
The factors of (r-1) can be added together to get the answer.
(r-1)(5r+7)
e + 1 13/16 = 2 5/16
subtract 1 13/16 from each side
e = 2 5/16 - 1 13/16
borrow from the 2
e = 1 16/16 + 5 /16 - 1 13/16
e = 1 21/16-1 13/16
e = 1 8 /16
e = 1 1/2
Average rate of change = [H(100) - H(80)] / (100 - 80)
H(100) = 0.003(100)^2 + 0.07(100) - 0.027 = 0.003(10000) + 0.07(100) - 0.027 = 30 + 7 - 0.027 = 36.973
H(80) = 0.003(80)^2 + 0.07(80) - 0.027 = 0.003(6400) + 0.07(80) - 0.027 = 19.2 + 5.6 - 0.027 = 24.773
Average rate of change = (36.973 - 24.773)/(100 - 80) = 12.2/20 = 0.61
Answer: B