Question

If $z$ varies as $px+y$ and if $z=3$, when $x=1$ and $y=2$. Also if $z=5$, when $x=2$ and $y=3$, find the value of $p$.

Answer 1

Let z=m $=(px+y)$ m being a constant Now z=3, x=3 and y=2 we have
$3=m(p+2)$ .....(i)
Again $z=5,x=2,y=3$ so $5=m(2p+3)$ ...(ii)
From (i) and (ii) we have $\frac{3}{5}=\frac{p+2}{2p+3}\Rightarrow p=1$