Solve for a: 1/a + 1/b = c

[Dale2010]

im a little confused here a little help would be appreciated

how would I solve for a in the following equation:

1/a + 1/b = c

i think you set it up like this: b + a = abc... but then what?

 

[mmm4444bot]

b + a = abc

but then what?

Get all of the terms that contain the symbol a to one side, with everything else on the other side.

Factor out a.

Divide.

 

[Dale2010]

Re: Solve for a

so is it :

a= b/b+c?


thanks for the help

 

[Dale2010]

Re: Solve for a

scratch that I meant:


a= b/bc-1

 

[mmm4444bot]

scratch that You can edit your posts here; click the [EDIT] button.


a= b/bc-1 This is correct, but it's not properly typed.

Typing b/bc-1 means \(\displaystyle \frac{b}{b} \cdot c - 1\)

When numerators or denominators are algebraic expressions, we need to type grouping symbols around them.

b/(bc - 1) is the proper way.

 

[JuicyBurger]

Re: Solve for a

Another way to solve this...

\(\displaystyle \frac{1}{a}+\frac{1}{b} = c\)

Subtract \(\displaystyle \frac{1}{b}\) from both sides...

\(\displaystyle \frac{1}{a}+\frac{1}{b} - \frac{1}{b} = c - \frac{1}{b}\)

This then equals...

\(\displaystyle \frac{1}{a} = c - \frac{1}{b}\)

Then, multiply both sides by \(\displaystyle a\) and divide both sides by what's on the right...

\(\displaystyle \frac{1}{c - \frac{1}{b}} = a\)

To simplify you can multiply the left by \(\displaystyle \frac{b}{b}\) and you will have the same answer =D

 

[emfn]

Re: Solve for a

The goal is to isolate a on one side of the equation.