Rewrite each formula as indicated below.

1. The distance an object has fallen under the force of gravity ($g$) is given by the formula $d =\frac { 1 } { 2 }gt^2$. Solve this formula for time, $t$ .

   Hint (a):

   First, isolate the $t^2$. Then undo the exponent.

   Answer (a):

   $t\ =\ \sqrt{\frac{2d}{g}}$ 

2. The area of a circle, $A$, is given by the formula $A = πr^2$. Solve this formula for the radius, $r$.

   Step (b):

   Divide by $π$.