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You can put this solution on YOUR website!
Two bikers started traveling at the same corner, one going south, the other going west.
\n" ); document.write( " One biker is traveling at 3 km/h faster than the other,
\n" ); document.write( " After one hour, the two bikers are 15 kilometers apart.
\n" ); document.write( " Find the rate of each.
\n" ); document.write( ":
\n" ); document.write( "Let s = the speed of the slower biker
\n" ); document.write( "then
\n" ); document.write( "(s+3) = speed to the faster
\n" ); document.write( "dist = speed * time, therefore:
\n" ); document.write( "1s = distance traveled by the slower in 1 hr
\n" ); document.write( "1(s+3) = distance traveled by the faster
\n" ); document.write( ":
\n" ); document.write( "this is a pythag problem a^2 + b^2 = c^2, in this problem
\n" ); document.write( "a = 1s
\n" ); document.write( "b = 1(s+3)
\n" ); document.write( "c = 15
\n" ); document.write( ":
\n" ); document.write( "we don't need the one, we have
\n" ); document.write( "s^2 + (s+3)^2 = 15^2
\n" ); document.write( ":
\n" ); document.write( "FOIL(s+3)(s+3)
\n" ); document.write( "s^2 + s^2 + 6s+ 9 = 225
\n" ); document.write( ":
\n" ); document.write( "combine on the left as a quadratic equation
\n" ); document.write( "2s^2 + 6s + 9 - 225 = 0
\n" ); document.write( "2s^2 + 6s - 216 = 0
\n" ); document.write( ":
\n" ); document.write( "simplify, divide by 2
\n" ); document.write( "s^2 + 3s - 108 = 0
\n" ); document.write( ":
\n" ); document.write( "Factors to
\n" ); document.write( "(s+12)(s-9) = 0
\n" ); document.write( ":
\n" ); document.write( "the positive solution is all we want here
\n" ); document.write( "s = 9 mph is the speed of the slower bike
\n" ); document.write( ":
\n" ); document.write( "You can find the rate of the faster one, check it in the pythag equation \n" ); document.write( "