# Algebra Ratio

1. Mar 15, 2013

### whatlifeforme

Is $\frac{x+y}{(x^2+y^2)}$ = $\frac{1}{x+y}$

would that be algebraically correct?

2. Mar 15, 2013

### gmax137

No, it is not.

3. Mar 15, 2013

### Staff: Mentor

whatlifeforme,
Would this be correct?

$$\frac{2 + 3}{2^2 + 3^2} = \frac{1}{2 + 3}$$

More simply, this is asking whether 5/13 is equal to 1/5.

4. Mar 15, 2013

### Vorde

And I want to add that your mistake is the so-called "freshman's dream", that is, the incorrect idea that $(x+y)^2=(x^2+y^2)$, which it does not.