Download Isosceles and Equilateral Triangles

Brett Solberg AHS ‘11-’12
1)
What does CPCTC mean? Explain it in your
own words.
Unscramble the letters to reveal a type of triangle.
2)
seicslose
3)
telqariulae
4)
giaqunearul
Do you want to review any HW problems?
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A triangle where exactly 2 sides
are congruent.
Legs – the 2 congruent sides
Vertex Angle – the angle
formed by the legs.
Base – Third side of the triangle.
Base Angles – 2 angles adjacent
to the base.
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Identify the legs, base, base angles, and
vertex of the triangle.
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Legs –
Base –
Base Angles –
Vertex –
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Identify the legs, base, base angles, and
vertex of the triangle.
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Legs –
Base –
Base Angles –
Vertex –
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Identify the legs, base, base angles, and
vertex of the triangle.
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Legs –
Base –
Base Angles –
Vertex –
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If two sides of a triangle are congruent, then
the angles opposite them are congruent.
If AB ≅ AC,
then ∠B ≅ ∠C
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If two angles of a triangle are congruent, then
the sides opposite them are congruent.
If ∠B ≅ ∠C
then AB ≅ AC
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Solve for y.
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Solve for x.
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Solver for x.
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Bisector
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Perpendicular Bisector
A
B
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The bisector of the vertex angle is the
perpendicular bisector of the base.
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Base Angles Theorem
Converse
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If a triangle is equilateral, then it is
equiangular.
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If a triangle is equiangular, than it is
equilateral.
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What is the measure of the angles of any
equiangular triangle?
What is the measure of the angles of any
equilateral triangle?
How many equilateral triangles are there in the trifoce?
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Find the value of x and y.
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If 2 sides of a triangle are congruent, than the
angles opposite them are congruent.
If two angles are congruent, then the sides
opposite them are congruent.
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If a triangle is equilateral, then it is
equiangular.
If a triangle is equiangular, then it is
equilateral.
The angles in any equilateral or equiangular
triangle are 60°.
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4.5 Worksheet and pg 230#1-13