Triangle Sum Theorem
Mrs. Reynolds says she can draw a triangle with angle measures 90°, 45°, and 45°. Is she correct? Explain your reasoning using what you know about the sum of the angles in a triangle.
Yes, because 90 + 45 + 45 = 180. The three angles inside the triangle need to add up to equal 180
Can the sides of a triangle have lengths: 4 inches, 9 inches, 3 inches
No, 3 + 4 < 9
A triangle has the following lengths and angles:
6 feet, 6 feet, and 7 feet
30°, 60°, 90°
What type of triangle is being described? (Hint: 2 words)
Isosceles Right Triangle
Angle A and Angle B are supplementary. Angle A is 38 degrees. What is the measure of angle B?
142
Right Angle
Hannah says she can draw a triangle with angle measures of 70°, 110°, and 40°. Is she correct? Explain your reasoning using what you know about the sum of the angles in a triangle.
No, because 70 + 110 + 40 = 220. The three angles inside the triangle need to add up to equal 180
Can the sides of a triangle have lengths: 10 inches, 4 inches, 7 inches
Yes, 4 + 7 > 10
A triangle has the following lengths and angles:
6 feet, 6 feet, and 6 feet
60°, 60°, 60°
What type of triangle is being described? (Hint: 2 words)
Equilateral Acute Triangle
Angle E and Angle G Complementary. Angle E is equal to 58 degrees. What is the measure of Angle G?
Angle G = 32 Degrees
Angles that add up to 90 degrees
Complementary Angles
There is a missing angle in a triangle. It is a right triangle and one of the angles is 70 degrees. What must the last angle of the triangle be?
20 degrees
Can the sides of a triangle have lengths: 6 inches, 4 inches, 10 inches
No, 6 + 4 = 10
A triangle has the following lengths and angles:
4 feet, 4 feet, and 6 feet
50°, 65°, 65°
What type of triangle is being described? (Hint: 2 words)
Isosceles Acute Triangle
Angle K and Angle L are Vertical angles. Angle K is 155 degrees. What is the measure of Angle L.
Angle L = 155 degrees
Angles that add up to 180 degrees
Supplementary Angles
A triangle has 35°, 58°, 63+x angles. Find x
x = 24°
A triangle has two short sides of length 11 and 9. What is the largest possible whole-number length for the long side?
19
A triangle has the following lengths and angles:
- 7 feet, 8 feet, and 12 feet
- 70°, 50°, 60°
What type of triangle is being described? (Hint: 2 words)
Acute Scalene Triangle
Angle E and Angle G are Supplementary. Angle E is equal to 85 and Angle G is equal to 2x+5. Find x.
x = 45 degrees
Angles that are across from each other that are equal.
Vertical Angles
Angle A of a triangle is 120 degrees. Angle B is (9x) degrees. Angle C is (3x) degrees. Find the value of x.
x = 5
A triangle has two short sides of length 21 and 10. What is the largest possible whole-number length for the long side?
30
A triangle has the following lengths and angles:
10 feet, 9 feet, and 8 feet
95°, 20°, 65°
What type of triangle is being described? (Hint: 2 words)
Scalene Obtuse Triangle
Angle S and Angle T are vertical triangles. Angle S is 95 degrees. Angle T is 3x+20. Find x.
x = 25
Angles that are next to each other. Share one side and the vertex.
Adjacent Angles