ISOSCELES TRIANGLES v parts of an isosceles triangle

ISOSCELES TRIANGLES v parts of an isosceles triangle v ITT

Parts of an Isosceles Triangle vertex angle the angle included by the congruent sides leg two congruent sides the side opposite base the vertex angle base angles that include the base

Isosceles Triangle Theorem (ITT) If two sides of a triangle are congruent, then the angles opposite those sides are congruent.

Corollary: An equilateral triangle is also equiangular. Corollary: Each angle of an equilateral triangle has a measure of 60.

Corollary: The bisector of the vertex angle of an isosceles triangle is also an altitude and a median of the triangle.

Converse of ITT If two angles of a triangle are congruent, then the sides opposite those angles are congruent. Corollary: An equiangular triangle is also equilateral.

Find the values of x and y. 3(y – 4)º 3 x - 2 x+4

Find the values of the variables. z x y 49

Find the values of the variables. y x z 58º w

Find the values of the variables. D C B m BCD = 130 x y z E w 18º 25º 20º A

B E A D C ABC is isosceles with base AC and BD is an altitude. If AD = 3 x + 1 and AC = 7 x – 6 : a. equation to solve for x b. value of x c. If AB = 32 cm, what is the perimeter of ABC?

B E A D C ABC is isosceles with base AC and BD is an altitude. If m A = 3 x – 1 and m ABC = 2(5 x + 3), a. equation to solve for x b. value of x c. m ABD

B E A D C ABC is isosceles with base AC and BD is an altitude. If BDC is isosceles with base BC and m C = 4 x – 3 , write the equation to solve for x and find the value of x.

Find the measures of the numbered angles. 35 8 1 4 2 6 28 10 9 7 3 5 100