what is 5x+3=54

hi,

first thing you'd want to do is subtract 3 from both sides of your equation -

$${\mathtt{5}}{\mathtt{\,\times\,}}{\mathtt{x}}{\mathtt{\,\small\textbf+\,}}{\mathtt{3}} = {\mathtt{54}}$$

$${\mathtt{5}}{\mathtt{\,\times\,}}{\mathtt{x}} = {\mathtt{51}}$$

then the final step is to just divide 51 by 5!

$${\mathtt{5}}{\mathtt{\,\times\,}}{\mathtt{x}} = {\mathtt{51}} \Rightarrow {\mathtt{x}} = {\frac{{\mathtt{51}}}{{\mathtt{5}}}} \Rightarrow {\mathtt{x}} = {\mathtt{10.2}}$$

so your final answer would be 10.2!

hope this helps!