<PRE><B>Question 931444</B>
x = wind speed
---
s = d/t
t = d/s
---
against the wind:
t = 720/(800 - x)
---
with the wind:
t = 880/(800 + x)
---
equate times:
720/(800 - x) = 880/(800 + x)
720*(800 + x) = 880*(800 - x)
720*800 + 720x = 880*800 - 880x
720x + 880x = 880*800 - 720*800
(720 + 880)x = 880*800 - 720*800
x = (880*800 - 720*800)/(720 + 880)
x = 80
---
answer:
wind speed = 80 kph
---
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
---
Convert fractions, decimals, and percents:
https://sooeet.com/math/fraction-decimal-percent.php
---
Calculate and graph the linear regression of any data set:
https://sooeet.com/math/linear-regression.php</PRE>