Question 215349: the perimeter of a square is 20 cm. find the length of the diangonal. Found 2 solutions by drj, MathTherapy:Answer by drj(1380) (Show Source):
Step 1. We'll use the Pythagorean Theorem which states that the sum of the square of the sides or legs of a right triangle is equal to the square of the hypotenuse or and for this example, c is the diagonal and a=b is the side since it's a square.
Step 2. So with a=b then or c=a*sqrt(2) and
Step 3. Perimeter P means that we add up all the form sides or or . If P=20, then or cm
Step 4. The diagonal is 7.07 cm.
I hope the above steps were helpful.
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You can put this solution on YOUR website! Since the perimeter of the square is 20 cm, then each side = cm
By letting diagonal equal D, and using the Pythagorean formula, , we get: ------- = 7.07
Therefore, length of the diagonal, or D = cm.
