# SPM Practice 2 -Question 8

Question 8

The variables x and y are related by the equation $y=\frac{p}{{3}^{x}}$  , where k is a constant.
Diagram below shows the straight line graph obtained by plotting ${\mathrm{log}}_{10}y$   against x.

(a) Express the equation $y=\frac{p}{{3}^{x}}$   in its linear form used to obtain the straight line graph shown in Diagram above.
(b) Find the value of p.

Solution