<PRE><B>Question 823750</B>
---
s = d / t
t = d / s
---
ride:
d = distance ridden
t = d/30
---
walk:
t = (171 - d)/4
---
total trip time:
7 = d/30 + (171 - d)/4
7 = 4d/120 + 30(171 - d)/120
7*120 = 4d + 30(171 - d)
840 = 4d + 5130 - 30d
-4290 = -26d
d = 165
---
answer:
time on bike:
t = 165/30
t = 5.5 hours
---
Solve and graph linear equations:
https://sooeet.com/math/linear-equation-solver.php
---
Solve quadratic equations, quadratic formula:
https://sooeet.com/math/quadratic-formula-solver.php
---
Solve systems of linear equations up to 6-equations 6-variables:
https://sooeet.com/math/system-of-linear-equations-solver.php</PRE>