Let's say the distance is "x".
time = distance / rate
time1 = x / 40
time2 = x/80
A) time1 shoud be twice time2 or (time1 / time2) =2
B) time1 -1 = time2
Substituting equation B) into A)
((time1 / (time1 -1) = 2
time1 = 2* time1 -2
time1 = 2 hours time2 = 1 hour
Distance = 80 miles
1st trip time1 = 80/40 = 2 hours
return trip time2 = 80/80 = 1 hour
total trip = 160 miles in 3 hours
average speed = 53.333333 miles per hour
Answer:
1
Step-by-step explanation:
2x^2 + x -1 = 2
2x^2 + x-1-2 = 0
2x^2 + x -3 = 0
2x^2 -2x + 3x-3 = 0
2x(x-1) + 3(x-1) = 0
(2x + 3)(x-1) = 0
2x + 3 = 0
or x-1 = 0
x = -3/2 or 1
