Given
Graph
Procedure
There are six important properties of parallelograms to know:
Opposite sides are congruent
Opposite angles are congruent
Consecutive angles are supplementary
If one angle is right, then all angles are right.
The diagonals of a parallelogram bisect each other.
First angle SPT
SPT = QRT
QRT = 180 - 81 -30
QRT = 69
SPT = 69
Value of x
20 = 4x - 12
4x = 20+12
4x = 32
x = 32/4
x = 8
Value of PR
5y-36 = y
4y = 36
y = 36/4
y = 9
PR = 2y
PR = 18
