Bell Work Note: The figures are not drawn to scale.

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Triangle Inequalities

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Presentation transcript:

Bell Work Note: The figures are not drawn to scale. Order the side lengths from least to greatest. Order the angle measurements from least to greatest. B A B C 7 in. 10 in. 9 in. 62° 65° 53° A C AB, AC, and BC <B, <A, <C

Finding an Angle Measure in a Triangle Find the value of x in the triangle shown. We know that: x + 83 + 26 = 180 x + 109 = 180 -109 -109 x = 71 So, the value of x is 71°. 26 83 x

You Try Find the value of x in the triangle shown. We know that: -118 -118 x = 62 So, the value of x is 71. 26 92 x

Note: The figures are not drawn to scale. You try! Note: The figures are not drawn to scale. A B C 27° 3x° 78° Find the value of x. B 82° 67° x° 3x + 27°+ 78°= 180° 3x + 105 = 180 -105 -105 3x = 75° x = 25° A C x + 82°+ 67°= 180° x + 149 = 180 -149 -149 x = 31°

Classifying Triangles by sides and angles Beat the Computer Drill

Review!

REMEMBER: YOU HAVE TO BEAT THE CLOCK! You only have 10 seconds! Directions: Classify each triangle by both its SIDES and its ANGLES. You will have 10 seconds before the computer shows you the answer. When the slide appears, as a group choose BOTH NAMES for the type of triangle and hold up your answer. REMEMBER: YOU HAVE TO BEAT THE CLOCK! You only have 10 seconds!

Trial Run Classify by sides: Classify by angles:

also also Isosceles Equilangular Triangle Triangle Classify by sides: Classify by angles: Equilateral Triangle Acute Triangle also Isosceles Triangle also Equilangular Triangle

Classify by sides: Classify by angles:

Classify by sides: Classify by angles: Isosceles Triangle Obtuse Triangle

Classify by sides: Classify by angles:

Classify by sides: Classify by angles: Isosceles Triangle Acute Triangle

Classify by sides: Classify by angles:

Classify by sides: Classify by angles: Scalene Triangle Obtuse Triangle

Classify by sides: Classify by angles:

Classify by sides: Classify by angles: Scalene Triangle Right Triangle

Classify by sides: Classify by angles:

Classify by sides: Classify by angles: Isosceles Triangle Right Triangle

Classify by sides: Classify by angles:

Classify by sides: Classify by angles: Scalene Triangle Acute Triangle

Classify by sides: Classify by angles:

Classify by sides: Classify by angles: Isosceles Triangle Obtuse Triangle

Classify by sides: Classify by angles:

Classify by sides: Classify by angles: Scalene Triangle Obtuse Triangle

Classify by sides: Classify by angles:

Classify by sides: Classify by angles: Scalene Triangle Acute Triangle

Classify by sides: Classify by angles:

Classify by sides: Classify by angles: Isosceles Triangle Right Triangle

Classify by sides: Classify by angles:

Classify by sides: Classify by angles: Isosceles Triangle Acute Triangle

Classify by sides: Classify by angles:

Classify by sides: Classify by angles: Scalene Triangle Right Triangle

Classify by sides: Classify by angles:

also also Isosceles Equilangular Triangle Triangle Classify by sides: Classify by angles: Equilateral Triangle Acute Triangle also Isosceles Triangle also Equilangular Triangle

Are you a triangle expert?

Review In order to form a triangle, the sum of the angles has to equal 180°. In order to form a triangle, the sum of the two smallest side lengths has to be GREATER than the third side. In a triangle, the largest angle is opposite the longest side. The smallest angle is opposite the shortest side. Skills Check will be on Thursday!!!

Practice