Answer
$T=\dfrac{wd}{rH}$
Work Step by Step
Multiply M to both sides of the equation to obtain:
$M \cdot r = \dfrac{12}{M} \cdot M
\\Mr = 12$
Divide $rH$ to both sides of the equation to obtain:
$\dfrac{wd}{rH} = \dfrac{rTH}{rH}$
Cancel common factors to obtain:
$\dfrac{wd}{rH} = T$
