SOLUTION: Sue rowed her boat across lake bend and back in 3hrs. If her rate returning was 2 mph less than the rate going, and if the distance each way was 7 miles, find her rate going.

Question 232547: Sue rowed her boat across lake bend and back in 3hrs. If her rate returning was 2 mph less than the rate going, and if the distance each way was 7 miles, find her rate going.
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
Sue rowed her boat across lake bend and back in 3hrs. If her rate returning was 2 mph less than the rate going, and if the distance each way was 7 miles, find her rate going.
------------
Going DATA:
rate = x mph ; distance = 7 miles ; time = d/r = 7/x hrs
-----------------------
Coming DATA:
rate = "x-2" mph ; distance = 7 miles ;time = d/r = 7/(x-2)
-------------------------------
Equation:
time + time = 3 hrs
7/x + 7/(x-2) = 3
Multiply thru by x(x-2):
7(x-2) + 7x = 3x(x-2)
7x-14 + 7x = 3x^2-6x
3x^2 - 20x + 14 = 0
x = 5.872 mph (this is her going rate)
========================================
Cheers,
Stan H.
RELATED QUESTIONS
Sue rowed her boat across Lake Bend and back in 3 hours. IF her rate returning was 3 mph... (answered by KMST)

Sue rowed her boat across Lake Bend and back in 3 hours. If her rate returning was 2 mph... (answered by mananth,Edwin McCravy)

Sue rowed her boat across and back lake bend in 3 hours. if her returning rate was 2mph... (answered by ankor@dixie-net.com)

Joan rowed her boat across Lake Placid and back in 3 hours. Her rate returning was 2 mph (answered by )

Sue rowed her boat across and back Lake Gaston in 3 Hours. If her rate rowing back was 2... (answered by TimothyLamb)

reem rowed her boat across lake dukan and back again in 3 hours if her speed coming back... (answered by josgarithmetic)

Helping my child do her math and could use some help. A person rowed her boat upstream (answered by ewatrrr)

Meg rowed her boat upstream a distance of 39 mi and then rowed back to the starting... (answered by stanbon)

Meg rowed her boat upstream a distance of 5 miles and then rowed back to the starting... (answered by mananth)