Question 957321
W=wind speed
{{{2015mi/(450mph+W)+2015mi/(450mph-W)=9hrs}}} Multiply by (450mph-W)(450mph+W)
{{{2015mi(450mph-W)+2015(450mph+W)=9hrs(450mph-W)(450mph+W)}}}
{{{906750(mi^2/hr)-2015W+906750(mi^2/hr)+2015W=(9)(202500(mi^2/hr^2)-W^2)}}}
{{{1813500(mi^2/hr)=1822500(mi^2/hr^2)-9W^2}}} Add 9W^2-1813500mi^2hr^2 to each side.
{{{9W^2=(9000)(mi^2/hr^2)}}} Divide each side by 9.
{{{W^2=(1000)(mi^2/hr^2)}}}Find square root of each side.
{{{W=31.62mph}}} ANSWER: The wind speed was 31.62 miles per hour.
CHECK:
{{{2015mi/(450mph-31.62mph)+2015mi/(450mph+31.62mph)=9hrs}}}
{{{2015mi/418.38mph+2015mi/481.62mph=9hrs}}}
{{{4.82hrs+4.18hrs=9hrs}}}
{{{9hrs=9hrs}}}