Two congruent triangles are created by the diagonals
Common Core Standard: G.GPE.7
What is perimeter? Perimeter is the distance around an object. If you measure the distance around a 2 dimensional shape, you have measured the perimeter.
The word perimeter is a combination of the Greek word peri which means around, and meter which is the unit of measure for distance.
Perimeter of parallelogram problems
Quick summary perimeter of parallelogram problems
Perimeter Problem 1. The length of two sides was given, therefore perimeter could be calculated by adding the length of the four sides. Because opposite sides of a parallelogram are equal, you could also use 2 x length + 2 x width.
Perimeter Problem 2. Only the length of one side was given. As a result you had to find one missing side of the parallelogram. Because of the properties of a parallelogram, the altitude can be used to find the missing side. The altitude creates a 30 60 90 triangle,and the hypotenuse is your missing side.