Properties of Parallelograms

Rectangle Properties

Characteristics of Rhombi:

• All Sides Are Congruent

• Diagonals Bisect Opposite Angles

• Diagonals Are Perpendicular (i.e., they form Right Angles)

All Squares Are Parallelograms...

...But Not All Parallelograms Are Squares. Why?

​If 2 parallel Lines are cut by a transversal, then...

• ​alternate interior angles are congruent

• ​alternate exterior angles are congruent

• ​corresponding angles are congruent

• ​same-side (consecutive) interior angles are supplementary

Parallel Slopes

• Parallel Slopes are the SAME as the original slope

• m=2, so IIm=2

• m=-1/3, so IIm=-1/3

• m=4/3, so IIm= 4/3

• y=6x-1, so m=6 and IIm=6

• y= -3/5x+1, so m=-3/5 and IIm=-3/5

Perpendicular Slopes

• Perpendicular Slopes are OPPOSITE RECIPROCALS

• m= -3/2 so Perpendicular m = 2/3

• m= -1/3 so Perpendicular m = 3/1

• m= 4/3 so Perpendicular m = -3/4

• m=2 so Perpendicular m = -1/2

• y= 6x-1 so Perpendicular m = -1/6

• y= -3/5x+2 so Perpendicular m = 5/3

Practice with Trig Functions