Classifying Triangles by Sides
What do you call a triangle with all three sides the same length?
Equilateral
What do you call a triangle with one right angle?
Right triangle
triangle has two angles: 50° and 60°. What is the missing angle?
(70°)
What is the perimeter of a triangle with sides 5 cm, 5 cm, and 5 cm?
(15 cm)
What is the formula to find the area of a triangle?
(½ × base × height)
What do you call a triangle with two sides the same length?
Isosceles
What do you call a triangle with all angles less than 90°?
(Acute triangle)
One angle is 90°, another is 45°. What's the third angle?
(45°)
Find the perimeter of a triangle with sides 4 in, 6 in, and 7 in.
(17 in)
Find the area: base = 10 cm, height = 5 cm.
(25 cm²)
What do you call a triangle with all sides different lengths?
Scalene
What do you call a triangle with one angle greater than 90°?
(Obtuse triangle)
A triangle has one angle that is 110° and another that is 40°. What’s the third angle?
(30°)
A triangle has two sides of 10 cm and 15 cm. The third side is missing. If the perimeter is 40 cm, what is the third side?
(15 cm)
A triangle has base = 8 in, height = 3 in. What is the area?
(12 in²)
True or False: An isosceles triangle can also be an acute triangle.
True
True or False: A triangle can have two right angles.
(False)
A triangle has angles x, 60°, and 50°. Solve for x.
(70°)
Find the perimeter: Triangle sides are 3.5 ft, 4.25 ft, and 6.75 ft.
(14.5 ft)
A triangle has area = 30 m² and base = 10 m. What is the height?
(6 m)
Which triangle by sides has the most possible different angles?
Scalene
A triangle has angles of 80°, 70°, and 30°. Classify it by its angles.
(Acute)
A triangle has one angle that is double the size of a 30° angle. The third angle is 60°. What are all three angles?
(30°, 60°, 90°)
An equilateral triangle has a perimeter of 27 cm. What is the length of one side?
(9 cm)
A triangle has base = 12 ft and height = 9 ft. Find the area.
A triangle has base = 12 ft and height = 9 ft. Find the area. (54 ft²)