Triangle Sum Theory

Triangle Sum Theorem

MA.8.GR.1.5

 

Solve problems involving the relationships of interior and exterior angles of a triangle.

 

Clarification 1: Problems include using the Triangle Sum Theorem and representing angle measures as algebraic expressions.

Triangle Sum Theorem

Things needed:

-Calculator

-No using of cellphone please.

-No opening of other Tab. Be focus. You can play or watch youtube only during free time after our lesson.

Triangle Sum Theorem

-Must get atleast 70% to receive a Price later

Open Ended

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Multiple Choice

What type of angle is this?

• Adjacent and Complementary

• Vertical and Supplementary

Multiple Choice

What type of angle is this?

• Adjacent and Supplementary

• Vertical and Complementary

Multiple Choice

What type of angle is this?

• Adjacent

• Vertical

Triangle Sum Theorem- using what you just learned, answer the following questions

Reminder: the angles of a triangle add up to 180 degrees!

Multiple Choice

Angles that are exactly 90 degrees are called _____ ______.

• tight angles

• acute angles

• obtuse angles

• right angles

Multiple Choice

Classify by angle.

• Obtuse

• Right

• Acute

Multiple Choice

The Triangle Sum Theorem states that the sum of all angles in a triangle is ______.

• 45°

• 90°

• 180°

• 360°

Multiple Choice

Will the following three angles for a triangle?

30°, 60°, 90°

(Guide: Just add them altogether and make sure it is a sum of 180°

• yes

• no

Multiple Choice

A student is trying to construct triangles using four different sets of angles. The angles in each set are given below. Which set will form a triangle?

(Guide: Just add the 3 numbers below and the correct answer will give you a sum of 180°)

• 45°, 65°, 70°

• 150°, 110°, 100°

• 50°, 50°, 50°

• 90°, 90°, 90°

Multiple Choice

A triangle has one angle that measure 45° and one that measures 60°. What is the measure of the third angle?

(Guide: 45 + 60 + X = 180)

• 135°

• 75°

• 120°

• 105°

Multiple Choice

Find the measure of the missing angle.

(Guide: 20° + 130° + x = 180°)

• 30^o

• 110^o

• 150^o

• 40^o

Multiple Choice

Find the measure of the indicated angle. 

(78° + 66° + X = 180°)

• 26

• 36

• 85

• 144

Multiple Choice

If 2 of the angles of a triangle are 30 and 70 degrees, the third angle measures...

(30° + 70° + X =180°)

• 80

• 100

• 60

• 90

Multiple Choice

Find the measure of the missing angle.

(40° + Right Angle + X = 180°)

• 90^o

• 10⁰

• 130^o

• 50^o

Multiple Choice

What is the C angle of a triangle whose A angle is 79 and the B angle is 43?

(A° + B° + X = 180°)

• 43

• 58

• 72

• 101

Multiple Choice

Find the measure of the angle indicated. 

• 139°

• 66°

• 138°

• 116°

Multiple Choice

Find the measure of < A.

• 25 degrees

• 35 degrees

• 40 degrees

• 45 degrees

Multiple Choice

Find the measure of < D.

• 45 degrees

• 60 degrees

• 90 degrees

• 30 degrees

Multiple Select

Name two remote interior angles of < 5.

• < 1

• < 2

• < 3

• < 4

​Test Your skills

Fill in the Blanks

Fill in the Blanks

Fill in the Blanks

Fill in the Blanks

Fill in the Blanks

Fill in the Blanks

Multiple Choice

The Triangle Sum Theorem states that the sum of all angles in a triangle is ______. 

• 45°

• 90°

• 180°

• 360°

Multiple Choice

What is the angle C of a triangle whose angle A is 79 and the angle B is 43?

(A + B + X = 180)

• 43

• 58

• 72

• 101

Multiple Choice

Find the measure of the missing angle.

(40 + Right Angle + X = 180)

• 90^o

• 10⁰

• 130^o

• 50^o

Multiple Choice

If 2 of the angles of a triangle are 30 and 70 degrees, the third angle measures...

(30 + 70 + X = 180)

• 80

• 100

• 60

• 90

Multiple Choice

Find the measure of the missing angle.

(40 + Right Angle + X = 180)

• 90^o

• 10⁰

• 130^o

• 50^o

Multiple Choice

In a TRIANGLE, how many TOTAL degrees are there?

• 100%

• 180 degrees

• it varies

• 360 degrees

Multiple Choice

Angles that are exactly 90 degrees are called _____ ______.

• tight angles

• acute angles

• obtuse angles

• right angles

Multiple Choice

Find the measure of each angle indicated. 

• 139°

• 66°

• 138°

• 116°

Multiple Choice

Find the measure of each angle indicated. 

60 + Right angle + X = 180

• 40°

• 33°

• 30°

• 29°

Multiple Choice

Solve for the missing angle measure.

• 47

• 57

• 53

• 133

Multiple Choice

Find the measure of the missing angle.

• 8^o

• 58^o

• 122^o

• 64^o

Multiple Choice

Find the measure of each angle indicated. 

• 140°

• 21°

• 105°

• 25°

Multiple Choice

What is the measure of the missing angle?

• 82

• 43

• 55

• 180

Multiple Choice

Find the measure of each angle indicated.

• 22

• 25

• 29

• 55

Multiple Choice

The Triangle Sum Theorem states that the sum of all angles in a triangle is ______. 

• 45°

• 90°

• 180°

• 360°

Multiple Choice

29 + 33 + X = 180°

• 151

• 147

• 118

• 62

Open Ended

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