# solving an equation

• Dec 4th 2011, 11:34 PM
juicysharpie
solving an equation
Hi,

I need some help solving an equation for y=17-x-(π/2)x. I solved for x earlier in the problem and got x=34/(π+4). I got as far as to y=17-(34/(π+4))-(π/2)(34/(π+4)) in solving the equation, but I'm not sure what to do next. The answer is 34/(π+4). Does anyone have any suggestions on what I should do?

Thank you in advance for the help!
• Dec 5th 2011, 12:35 AM
sbhatnagar
Re: solving an equation
You are supposed to make a common denominator.
$\displaystyle y=17-x - x{\left (\frac{\pi}{2}\right)}$

Quote:

$\displaystyle \text{Substitute} \hspace{4} :$ $\displaystyle x=\frac{34}{(\pi+4)}$.
\displaystyle \begin{align*} y &= 17-x-x{\left (\frac{\pi}{2}\right)} \\ &= 17-\frac{34}{(\pi+4)} -{\left (\frac{34}{(\pi+4)}\right)}{\left (\frac{\pi}{2}\right)} \\ &= 17- \left( \frac{34}{\pi+4}\right) {\left ( \frac{2+\pi}{2}\right)} \\ &=\frac{34(\pi+4)-34(2+\pi)}{2(\pi+4)} \\ &= \frac{34\pi-34\pi+34(4)-34(2)}{2(\pi+4)} \\ &=\frac{34(2)}{2(\pi+4)}\\ &= \frac{34}{\pi+4}\end{align*}