Expert Answers
beckden eNotes educator| Certified Educator

`c=(ab)/(a+b)` solve for a

first multiply both sides by (a+b) to get rid of fraction


Now distribute


Now we want to get all the terms with a as a factor on one side and everything else on the other


now factor out the a


Now divide by `c-b`


And we can get rid of the negative sign by noting `(c-b)=-(b-c)`

To get our final answer `a = (bc)/(b-c)`

Wiggin42 | Student

c=(ab) / (a+b)

Get rid of the fraction: 

c (a + b) = ab 

ac + bc = ab Distributive Property

ac - ab = -bc Isolating the variable we want to one side

a (c - b) = = -bc 

a = -bc / (c-b)