Answer:
12
Step-by-step explanation:
Well, 12/12=1, which I guess is the smallest number we can get, and 12 is divisible by 2 too.
Let s = northbound train
Then
2s = southbound train
:
Distance = time * speed
4s + 4(2s) = 600
:
4s + 8s = 600
:
12s = 600
:
s = 600/12
:
s = 50 mph is the northbound train
Then
2(50) = 100 mph is the southbound train
:
:
Check:
4(50) + 4(100) = 600
Answer:
C
Step-by-step explanation:
Simply
3Y+-21=12X
Re-order the terms
-21+3Y=12X
(Solving for Y variable)
Move all terms containing y to the left, all other terms to the right.
Add 21 to each side of the equation
-21+21+3Y=21+12X
Combine like terms: -21+21=0
0+3Y=21+12X
3Y=21+12X
Divide each side by 3
Y=7+4X
Simplifying
Y=7+4x
I hope this helps!! :)