Answer:
Step-by-step explanation:
you have to use the midpoint formula which is
so you plug your numbers in
Add the tops
if possible simplify
and that is your answer
Answer:
D
Step-by-step explanation:
When you put something in parenthesis by a number, your multiplying each individual number by the number outside of parenthesis. Therefore, 5(2) = 10 and 5(7) = 35 and that equals 45, and 5(2+7) you distribute the 5 to both numbers and get 10+35 which equals 45 aswell.
We have to assume that the speed before being stuck was sufficient to get to the destination on time had there been no delay. Call that speed "s" in km/h.
Since 200 km is "halfway", the total distance must be 400 km.
time = distance / speed
total time = (time for first half) + (delay) + (time for second half)
400/s = 200/s + 1 + 200/(s+10) . . . .times are in hours, distances in km
200/s = 1 + 200/(s+10) . . . . . . . . . . subtract 200/s
200(s+10) = s(s+10) +200s . . . . . . .multiply by s(s+10)
0 = s² +10s - 2000 . . . . . . . . . . . . . .subtract the left side
(s+50)(s-40) = 0
Solutions are s = -50, s = 40
The speed of the bus before the traffic holdup was 40 km/h.
