Rearranging into $y=mx+c$ format and finding unknowns $a$ and $b$ 
Two quantities $x$ and $y$ are connected by a law $y = \frac{a}{1-bx^2}$ where $a$ and $b$ are constants. Experimental values of $x$ and $y$ are given in the table below:
  $$
\begin{array}{|l|l|l|l|l|l|}
\hline
x & 6 &8 & 10 & 11 & 12\\
\hline
y & 5.50 & 6.76 & 9.10 & 11.60 & 16.67\\\hline 
\end{array}
$$
  By plotting a suitable graph, find $a$ and $b$. (Use tables correct to $2$ significant figures in your work)

I dont know whether or not i should use logs to rearrange the equation into $y=mx+c$ format. 

When you are asked questions like this one, basically the problem is to find the change of variables which transform the equation into the equation of a straight line. So, starting with $$y = \frac{a}{1-bx^2}$$ rewrite $$\frac 1y=\frac{1-bx^2}{a}=\frac 1a-\frac ba x^2$$
I am sure that you can take from here.
