Solving equation

Hi,
When I solve Solve 1/5(x-4)=3 I would multiply the denominator by everything inside the brackets and the 3 after the equal sign to get rid of the fration then expand by the brackets but why is it that you only multiply the 5 by the 3 then expand and solve because to my knowledge you always multiply everything on each side of the equation ?
Thanks

I didn't follow through any of that... Why would you multiply the denominator by everything inside the bracket??

$\frac{1}{5}(x-4)=3$

The first thing you want to do when you're solving for $x$ is to recognise what is happening on both sides. So here you have a fifth of (x-4) and on the other you just have a 3, so the first step is to get rid off the fraction by multiplying by what we call the reciprocal - and the reciprocal of 1/5 is 5. Which then leads us to $5\cdot \frac{1}{5}(x-4)=\frac{5}{5}(x-4)=1(x-4)=x-4$ which makes our LHS much simpler, but since we multiplied by 5 on the LHS, we also need to multiply by 5 on the RHS giving us $3\cdot 5=15$ thus we have $x-4=15$ and we repeat the same idea with different operations involved to get $x$ on its own.

I'm not entire sure what you are trying to do from your post...

Thanks , basically what im trying to say is that I thought you multiply the same thing by either side of the equation?