algebra help

[Guest]

1. during the first part of a trip a canoeist travels 86 miles at a certain speed. The canoeist travels 6 miles on the second part of the trip at a speed 5mph slower. The total time for the trip is 4hrs, what was the speed on each part of the trip?

2. solve
W^4 – 6w² - 2 = 0

 

[Deleted member 4993]

1. during the first part of a trip a canoeist travels 86 miles at a certain speed. The canoeist travels 6 miles on the second part of the trip at a speed 5mph slower. The total time for the trip is 4hrs, what was the speed on each part of the trip?

Assume

for the first part of the trip the speed of the canoe was = v mph ? time to travel 86 miles = ??

for the second part of the trip the speed of the canoe was = (v-5) mph ? time to travel 6 miles = ??

Add up the time - equate to 4 - solve for 'v'.


2. solve
W^4 – 6w² - 2 = 0 (assuming "W" and "w" are same variable)

Substitute u = w[sup:3srfdpfd]2[/sup:3srfdpfd] - solve the quadratic for "u" - solve for "w"

Please show your work, indicating exactly where you are stuck - so that we may know where to begin to help you.