Equations and how to do them

Question

Solve $$\frac{1}{3n}=\frac{3}{4(2n-1)}$$ please explain how to do this and why you have to change signs from positive to negative or vise versa.

How to typeset, part I: To render $\frac {1}{3}n = \frac{3}{4}(2n-1)$, type $\frac {1}{3}n = \frac{3}{4}(2n-1)$ . Or to render $\frac {1}{3n} = \frac{3}{4(2n-1)}$, type $\frac {1}{3n} = \frac{3}{4(2n-1)}$ . — got it--thanks, Sep 26 '15 at 22:37
@Anaymous, please double check that the above edit is correct. — John_dydx, Sep 26 '15 at 22:39

score 1 · Answer 1 · answered Sep 26 '15 at 22:56

1

Taking the reciprocal of each side yields:

$$3n=\frac{4}{3}(2n-1)=\frac{8}{3}n-\frac{4}{3}$$

Therefore,

$$\frac{n+4}{3}=0$$

Therefore $n=-4$.

answered Sep 26 '15 at 22:56

Aleksandar

score 1 · Answer 2 · answered Sep 26 '15 at 23:08

1

$$\frac {1}{3n}= \frac{3}{4(2n-1)}$$ $$4(2n-1)=9n$$ $$8n-4=9n$$ $$-4=n$$

answered Sep 26 '15 at 23:08

ejgal

2 Answers2