They're parallel because they have the same slope.
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.
The equation given in the question is
2s + s + 12 = 132
3s + 12 = 132
3s = 132 - 12
3s = 120
s = 120/3
= 40
From the above deduction we can see that the value of the unknown variable comes out to be exactly 40. This is possible because there is a single unknown variable and a single equation to get the value of the variable from. So the correct option among all the options given in the question is option "D".
Nancy's rate=27 mph
Greg's rate=45 mph
t=Greg's time
t+2=Nancy's time
Since they both traveled same distance then:
27(t+2)=45t
27t+54=45t
18t=54
t=3 hours
Greg will pass Nancy after 3 hours
Answer:
D. x = 7
Step-by-step explanation:
NOTE : <u><em>there should be an equal sign somewhere in the given expression.</em></u>
suppose the equation is the following:
3(x-4)-5 = x-3
………………………………………………………
3(x - 4) - 5 = x - 3
⇔ 3x - 12 - 5 = x - 3
⇔ 3x - 17 = x - 3
⇔ 3x - 17 + 17= x - 3 + 17
⇔ 3x = x + 14
⇔ 2x = 14
⇔ x = 14/2
⇔ x = 7
