Warm-up

Legs: Congruent sidesOf an isosceles triangleBase: Third side of anIsosceles triangleVertex Angle: the angle the two legs formBase Angle: the angle formed by the leg and the base

If the two legs are congruent, then the base angles are congruent

The converse is also true.

If _______________ are congruent, then _____________are congruent.

• If we can prove a triangle to be isosceles, then we can prove two angles to be perpendicular, and we can prove that line of symmetry to be a midpoint.

• What is the value of x?

• When you are finished with your quiz…

• You are to work on Pg. 254 #6 – 13, 16-19