2. Write a proof for the biconditional using the conditional and converse.

A triangle is equilateral if and only if all the side lengths of the
triangle are equal.

3. Write a proof for the biconditional using the inverse and
contrapositive.
x24 if and only if 3x 12.

Write a proof for this statement. If a quadrilateral is a square, then the quadrilateral is a rectangle.