Question 68826
 solve for x for this equation: 

{{{(1/x)=(1/y)+(1/z)}}}
:
Put the right side over a common denominator:
{{{(1/x) = ((z + y)/yz)}}}
:
Cross multiply:
x(z + y) = yz
:
Divide both sides by (z+y) and you have:
x = {{{((yz)/(z+y))}}}