<span>Answer:
Roma Sherry drove 330 miles from her hometown to Tucson. During her return trip, she was able to increase her speed by 11 mph. If her return trip took 1 hour less time, find her original speed and her speed returning home.
:
Let s = original speed
then
(s+11) = return speed
:
Write a time equation: Time = distance%2Fspeed
:
Original time = return time + 1 hr
330%2Fs = 330%2F%28%28s%2B11%29%29 + 1
:
Multiply equation by s(s+11) and you have:
330(s+11) = 330s + s(s+11)
:
330s + 3630 = 330s + s^2 + 11s
:
0 = 330s - 330s + s^2 + 11s - 3630
:
A quadratic equation:
s^2 + 11s - 3630 = 0
Factor this to:
(s + 66)(s - 55) = 0
Positive solution
s = 55 mph is original speed.
:
Find the time
330/55 = 6 hr, original time
and
330/66 = 5 hrs, faster time; confirms our solution.</span>
Yes you are correct B is the right answer
Answer:
163 miles
Step-by-step explanation:
set up a ratio based on 49 miles in 1 hour (60 minutes):
let 'd' = distance in 3hrs, 20 min
3hrs, 20 min = 200 minutes
49/60 = d/200
cross-multiply:
60d = 9800
d = 163.3
1/9 on a calculator is 0.11111111
Answer:
The correct option is;
r = √(x² + y²)
θ = tan⁻¹(y/x)
Step-by-step explanation:
The rectangular coordinate of a complex number on the complex plane is given as (x, y)
Given that the complex number is represented by a point on the plane, we have;
The distance, r, of the point from the origin, (0, 0) is r = √(x² + y²)
The direction, θ, by which we rotate to be in line with the point on the complex number is given by tan⁻¹(y/x)
