One of the diagonals of a parallelogram is its altitude. What is the length of this altitude, if its perimeter is 50cm, and the length of one side is 1cm longer than the length of the other?
Let ABCD be this parallelogram AB + BC + CD + DA = 50, but AD = BC and AB = DC, Then: 2.AD + 2.AB = 50 and : AD+AB = 25 . We also know that AB+1 = AD (Given), then: AD + (AD+1) = 25 2.AD = 24 AD = 12, THEN AB = 12+1=13 Calculate DB the diagonal perpendicular to AD, using Pythagoras: