Classify Triangles, Sides of Triangles, Triangle Sum, Exterior Angles

The exterior (outside) angle of a triangle is equal to the WHAT of the two opposite interior angles?

Classify the triangle.

• acute

• equiangular

• right

• obtuse

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

• 45°

• 90°

• 180°

• 360°

Find the measure of the angle indicated. 

• 139°

• 66°

• 138°

• 116°

What is the third angle of a triangle whose 1st angle is 79 and the 2nd angle is 43?

• 43

• 58

• 72

• 101

Find the measure of the missing angle.

• 90^o

• 10⁰

• 130^o

• 50^o

Solve for x.

• 16

• 11

• 50

• 6

If all three angles are exactly the same measure, how big is each angle?
Hint:    x + x + x  = 180

• 180 degrees

• 90 degrees

• 50 degrees

• 60 degrees

What is the measure of x?

• 101°

• 111°

• 121°

• 131°

Set up an equation to find x.

• 42 + 8x = 2 + 12x

• 2 + 12x + 42 = 8x

• 42 + 8x + 2 + 12x = 180

• 42 + 8x = 180