Question

Hermina cut a 10'' by 15'' piece of cardboard down the diagonal. A rectangle is 10 inches wide and 15 inches long. A diagonal cut is shown with a line labeled c. The cut divides the rectangle in half and creates two right triangles. The hypotenuse of each right triangle is the line labeled c. What is the length c of the cut, in inches?

Answer 1

18.03 inches

Explanation:

The cardboard is cut as shown below.

The line c cuts the rectangle into 2 right angled triangles.

To find the diagonal (hypotenuse), we have to apply Pythagoras Rule:

`hyp^2 = opp^2 + adj^2\\\\=> c^2 = 10^2 + 15^2\\\\c^2 = 100 + 225 = 325\\\\`

=> c = 18.03" = 18.03 inches

The length of c, the diagonal, is 18.03 inches.