The variable $\displaystyle x $ and $\displaystyle y$ are related by the equation $\displaystyle y = kH^x$, where $\displaystyle k $ and $\displaystyle H$ are constant.Diagram shows the straight line graph obtained by plotting $\displaystyle log_4{y}$ against $\displaystyle x$

a)express the equation in its linear form used to obtained the straight line graph shown in diagram.