Answer:
- 3 hours
- 1 hour 45 minutes
- 300 miles
Step-by-step explanation:
1. The trains are moving toward each other at a total speed of 50 +20 = 70 miles per hour. Together, they cover the 210 mile distance in ...
time = distance/speed
time = 210 mi/(70 mi/h) = 3 h
The trains collide after 3 hours.
__
2. The fly is closing with the freight train at a speed of 100 +20 = 120 miles per hour. Together, the fly and the train cover the initial 210 mile distance in ...
(210 mi)/(120 mi/h) = 7/4 h = 1 hour 45 minutes
The fly first meets the oncoming freight train after 1 h 45 min.
__
3. The fly is flying for all three hours before the trains collide, so, at 100 miles per hour, will fly 300 miles.
2x + 5y + 7x
---
Combine like terms
(2x + 7x)
---
9x + 5y
Answer:
Step-by-step explanation:
1) -28r +14=-12r-2
-16r=-16
r=1
~~~~~~~~~~~~~~~~
2) -35x+5=6x-36
-41x=-41
x=1
The answer is D, which is 32. Hope this helps.
