SOLUTION: Laura's friend, Sasha, lives 1 mile away. Laura rode her bike to Sasha's house. On her way back home, Laura rode at an average speed that was 2 miles per hour less than on her wa

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Question 1064890: Laura's friend, Sasha, lives 1 mile away. Laura rode her bike to Sasha's house. On her way back home, Laura rode at an average speed that was 2 miles per hour less than on her way to Sasha's house, so it took her 5 minutes longer. The equation below represents this situation.
1/x-2-1/x=1/12
Part A:
On the number line below, plot the average speed, in miles per hour, at which Laura rode her bike on her way to Sasha's house.
Found 2 solutions by josgarithmetic, MathTherapy:
Answer by josgarithmetic(39614) About Me  (Show Source):
You can put this solution on YOUR website!
Let r be speed going and let t be time in going.
Fill the Rate-time-distance table: 

             speed    time    distance

GOING          r        t      1

RETURNING    r-2      t+1/12   1

If you work through this system system%28rt=1%2C%28r-2%29%28t%2B1%2F12%29=1%29, you should be able to find an equation highlight%28r%5E2-2r-24=0%29.

r%5E2-2r-24=0
%28r-6%29%28r%2B4%29=0
The positive solution is needed.
r-6=0
highlight_green%28r=6%29

cross%28system%28r=1%2Bsqrt%2813%29%2Cor%2Chighlight%28r=4.6%29%29%29

Answer by MathTherapy(10549) About Me  (Show Source):
You can put this solution on YOUR website!
Laura's friend, Sasha, lives 1 mile away. Laura rode her bike to Sasha's house. On her way back home, Laura rode at an average speed that was 2 miles per hour less than on her way to Sasha's house, so it took her 5 minutes longer. The equation below represents this situation.
1/x-2-1/x=1/12
Part A:
On the number line below, plot the average speed, in miles per hour, at which Laura rode her bike on her way to Sasha's house.
You better not follow the other person's "so-called" solution, unless you want to fail.

Correct answer: 

By the way, your equation is CORRECT, so DO NOT CHANGE it to anything RIDICULOUSLY CONFUSING and/or COMPLEX. There's absolutely no need to do so.