Question 811298
Person____________speed_____________time______________distance
Steve_____________r+20______________x-1.25____________300
Bob_______________r_________________x_________________300


We do not know Bob's speed, r and we do not know Bob's time, x.  We only know their distance to travel.  Use uniform rate R*T=D, and D is the same for both Steve and Bob.


{{{(r+20)(x-1.25)=300}}} and {{{r*x=300}}}


{{{rx+r(-1.25)+20x+20*(-1.25)=300}}}
{{{rx-1.25r+20x-25=300}}}
Seeing the equality of rx and 300, we can subtract either from both sides to simplify this equation to {{{-1.25r+20x-25=0}}}
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We now have the simpler system, {{{1.25r-20x+25=0}}} and {{{rx=300}}}
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Solve the rx equation for x and substitute:
x=300/r
giving one equation in only r:   {{{highlight(1.25r-20(300/r)+25=0)}}}-----take it from there.