Answer: it will take them 4 hours to be 640 kilometers apart.
Step-by-step explanation:
Let t represent the time it will take for both trains to be 640 kilometers apart. It means that the total distance that both trains will covered in t hours is 640 kilometers.
Distance = speed × time
A train leaves Little Rock Arkansas and travels north at 75 kilometers per hour. Distance covered after t hours would be 75 × t = 75t
Another train leaves at the same time and travels south at 85 kilometers per hour. Distance covered after t hours would be 85 × t = 85t
Since the total distance covered is 640 kilometers, then
75t + 85t = 640
160t = 649
t = 640/160
t = 4 hours
Answer:
width = 15 inches
length = 36 inches
Step-by-step explanation:
To solve you need to find the width...
width = w
length = 2w + 6
the perimeter is all the way around the area, so..
2w + 2(2w + 6) = 102
because there are 2 widths and 2 lengths in a perimeter.
Solve for w:
2w + 4w + 12 = 102
subtract 12 from both sides and combine like terms...
6w = 90
divide both sides by 6...
w = 15
the width = 15, and the length = 2(15) + 6 = 36
-2 (x-2y=-5)
-2x+4y=10
2x+3y=4
0+7y=14
/7. /7
y=2
2x+3 (2)=4
2x+6=4
-6. -6
2x=-2
/2. /2
x=-1
Answer:
5.5 or 5.50.
Step-by-step explanation:
2.75 x 3 = 8.25. that minus 2.75 = 5.50.