Question

Daniela needs to cut a rectangular hole in a wall where a new window will be installed. The window will be 4 feet high and 3 feet wide. She draws the outline for the window on the wall. If the only measurement tool that she has is a measuring tape, how can she be sure the shape she drew is a rectangle?

Answer 1

Measure the diagonals, they should be 5 feet (3,4,5 triangle).

Explanation:

As a more general answer, the diagonal measurements of ANY rectangle will be equal. You can calculate the correct measurement using A^2 + B^2 = C^2. A and B are the lengths of the sides and C is the length of the diagonals.