+72 \(0.25r-0.125+0.5r=0.5+r\) First, you combine like terms.
\((0.25r+0.5r)-0.125=0.5+r\)
\(0.75r-0.125=0.5+r\) Then, you subtract r from both sides.
- r = - r
\(-0.25r-0.125=0.5\) Then, you subtract 0.125 from both sides.
- 0.125 = -0.125
\(-0.25r=0.375\) Then, because you can't have a neagtive
variable, you multiply both sides by -1.
\(-0.25r*-1=0.375*-1\)
\(0.25r=-0.377\) Finally, you divide both sides by 0.25.
\(\frac{0.25r}{0.25}=\frac{-0.375}{0.25}\)
\(r=-1.5\)
Hope this helps!
-RedGlasses 
+2446 It took me a long time to spot the error in your calculation, but I finally found it! By the way, alignment is always a tricky subject, but you did very well!
However, here is where your error was made. Now, my alignment skills are not up to par either, so bare with me please:
\(-0.25r-0.125=0.5\)
-0.125 -0.125
--------------------------------------
\(-0.25r=\hspace{1cm}0.375\)
However, this is incorrect. It should be the following!
\(-0.25r-0.125=0.5\)
+0.125 +0.125
--------------------------------------
\(-0.25r=\textcolor{red}{0.625}\)
Now, when you solve from here, you will get that \(r=-2.5\).
+72 I'm sorry, I tried to make all of the words line up, but they didn't. I hope all of what I just said makes sense.
-RedGlasses
