D/60 + D/50 = 2D/55 - 1/2
find common denominator ( 3300)
3300/60 = 55
3300/50 = 66
3300/55=60
so then you get 55D +66D= 60(2D)-1650
121D=120D-1650
D=1650 miles
check
1650/60 =27.5, 1650/50 = 33, 27.5 + 33 = 60.5 hours total
1650/55 = 30, 30 x 2 = 60
60.5-60 = 0.5 longer
so distance = 1650 miles
Answer:
thanks
Step-by-step explanation:
Using proportions, it is found that the speed of the runners are of 16 mph and of 20 mph.
<h3>What is a proportion?</h3>
A proportion is a fraction of a total amount.
After 30 minutes, the runners are 2 miles apart, hence the second runner is 4 miles per hour faster than the second, that is:
.
The first runner's speed is 4/5 of the speed of the second runner, hence:





Hence, the speed of the runners are of 16 mph and of 20 mph.
More can be learned about proportions at brainly.com/question/24863377
Answer:
7y^2 - y^2z - 10yz-5
C. 7 y squared minus y squared z minus 10 y z minus 5
Step-by-step explanation:
A. y squared minus y squared z minus 10 y z minus 5
B. y squared minus y squared z minus 5 y z minus 5
C. 7 y squared minus y squared z minus 10 y z minus 5
D. 7 y squared minus y squared z minus 2 y z minus 5
Given:
3y^2 - 6yz - 7 + 4y^2 - 4yz + 2 - y^2z
Collect like terms in the expression
3y^2 + 4y^2 - 6yz - 4yz - y^2z - 7 + 2
Simplify
7y^2 - 10yz - y^2z - 5
Rewritten as
7y^2 - y^2z - 10yz-5
Option C. 7 y squared minus y squared z minus 10 y z minus 5
Is the answer