# Cannot Solve for z

1. Jan 2, 2009

### totty3478

Hi,

I have recently returned to education after 15 years out and I am finding that it is my basic maths that causes me the most problems. I have the following equation

x = y (1-z)/ $$\pi$$ $$\sqrt{}z$$

so you know, thats pi multiplied by root z.

and I cant solve for z, can someone rearrange this equation for me.

thanks

2. Jan 2, 2009

Do you mean
$$x= \ffrac{y(1-z)}{\pi\sqrt{z}}[/itex]? That would be the same as $\pi x\sqrt{z}= y- yz$ or $yz+ \pi x\sqrt{z}- y= 0[itex]. Let [itex]u= \sqrt{z}$ so that $u^2= z$. Then the equation becomes $yu^2+ \pi xu+ y= 0$, a quadratic equation for u. That can be solved using the quadratic formula and then square u to find z. 3. Jan 2, 2009 ### NoMoreExams To me that kind of looked like: [tex] x = \frac{y(1-z)}{\sqrt[\pi]{z}}$$

But it could be anything.

4. Jan 2, 2009

### totty3478

sorry I will try again, the equation should be

$$x = \frac{y(1-z)}{\pi\sqrt{z}}$$

then solve for z

thanks

Last edited: Jan 2, 2009
5. Jan 2, 2009

### tim_lou

substitute $$z'=\sqrt{z}$$ and you get a quadratic eq.. Then multiply both sides by $\pi z'$

6. Jan 2, 2009

### totty3478

Thanks guys, I got the answer i was looking for after I made it into a quadratic.