Classifying Triangles by Sides & Angles

Classification of Triangles

Dr. Tom Giles

Classification of Triangles

Dr. Tom Giles

Open Ended

What do you know about triangles?

Classification of Triangles by SIDES

• Isosceles Triangle - Two Congruent Sides

• Scalene Triangle - No Congruent Sides

• Equilateral Triangle - Three Congruent Sides

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Multiple Choice

Which would be the best classification for the triangle shown?

• acute isosceles

• right scalene

• acute scalene

• obtuse scalene

Multiple Choice

Which would be the best classification for the triangle shown?

• acute isosceles
• obtuse scalene
• obtuse isosceles
• acute scalene

Multiple Choice

Which would be the best classification for the triangle shown?

• right isosceles
• obtuse scalene
• obtuse isosceles
• acute scalene

Multiple Choice

Which angle is the vertex angle?

• <C
• <A
• <B

Multiple Choice

Which segment is the base?

• Segment AB
• Segment BC
• Segment AC

Classification of Triangles by ANGLES

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​Solve for X

​Solve for X

​Solve for X

​Solve for X

Triangle Sum Theorem

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How do we use all this information about triangles to solve problems?

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Multiple Choice

Which would be the best classification for the triangle shown?

• acute isosceles

• right scalene

• acute scalene

• obtuse scalene

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Multiple Choice

Which would be the best classification for the triangle shown?

• acute isosceles

• equiangular scalene

• equiangular isosceles

• equiangular equilateral

Multiple Choice

Which would be the best classification for the triangle shown?

• acute isosceles
• obtuse scalene
• obtuse isosceles
• acute scalene

Multiple Choice

Which would be the best classification for the triangle shown?

• right isosceles
• obtuse scalene
• obtuse isosceles
• right scalene

Multiple Choice

Which would be the best classification for the triangle shown?

• right isosceles
• obtuse scalene
• obtuse isosceles
• acute scalene

Multiple Choice

What is the value of the missing angle?

• 61
• 50
• 60
• 69

Multiple Choice

What is the value of x?

• 60
• 5
• 10
• -3

Multiple Choice

What is the value of x?

• 10
• 5
• -12
• 9

Multiple Choice

What is the value of x?

• 64
• 46
• 127
• 38

Multiple Choice

What is the value of x?

• 75
• 80
• 63
• 60

Multiple Choice

What is the value of the ANGLE A (not just x)?

• 151
• 68
• 151
• 70

Multiple Choice

What is the value of x?

• 30
• 45
• 47
• 50

Multiple Choice

Which angle is the vertex angle?

• <C
• <A
• <B

Multiple Choice

Which segment is the base?

• Segment AB
• Segment BC
• Segment AC

Multiple Choice

What is the value of x?

• 51
• 49
• 78

Multiple Choice

What is the measure of angle 2?

• 50
• 65
• 115