Answer:
c
Step-by-step explanation:
i had this problem before so i know
The formula for the sum of the a finite geometric series is this:
Sn = a((1-r^n) / (1-r))
The given values are:
n = 30
a = 0.5 mi
r = 1.10 (10% more each day)
S30 = 0.5 ((1-1.10^30) / (1-1.10))
S30 = 82.25 mi
After 30 days, he will have traveled 82.25 miles.
10(x^2) = 80x
(divide by the 10)
x^2 = 8x
which also equals
(x)(x) = 8x
(divide by x)
x = 8