Triangle Basics
What do all angles inside a triangle add up to?
180°
What is the formula for the perimeter of a triangle?
P = side + side + side
What is the distance from the centre of a circle to the outside edge called?
Radius.
What type of triangle do we use the Pythagorean theorem with?
Right triangle.
A garden is shaped like a triangle. The sides are 4 m, 6 m, and 7 m. What is the perimeter?
4 + 6 + 7 = 17 m
A triangle has side lengths of 5 cm, 5 cm, and 8 cm. What type of triangle is it?
Isosceles triangle.
Find the perimeter of a triangle with sides 6 cm, 8 cm, and 10 cm.
6 + 8 + 10 = 24 cm
What is the distance all the way across a circle through the centre called?
Diameter.
What is the Pythagorean theorem formula?
a² + b² = c²
A triangular sign has a base of 10 cm and a height of 6 cm. What is its area?
10 × 6 ÷ 2 = 30 cm²
A triangle has angles of 60°, 60°, and 60°. What type of triangle is it?
Equilateral triangle.
What is the formula for the area of a triangle?
A = base × height ÷ 2
If the radius of a circle is 4 cm, what is the diameter?
4 × 2 = 8 cm
In a right triangle, what is the longest side called?
Hypotenuse.
A circular table has a diameter of 2 m. What is its circumference? Use π = 3.14.
C = πd
C = 3.14 × 2
C = 6.28 m
A triangle has angles of 90°, 40°, and 50°. What type of triangle is it?
Right triangle.
Find the area of a triangle with a base of 12 cm and a height of 5 cm.
12 × 5 ÷ 2 = 30
30 cm²
What is the formula for circumference?
C = πd
or
C = 2πr
Find the hypotenuse if a = 3 cm and b = 4 cm.
3² + 4² = c²
9 + 16 = c²
25 = c²
c = 5 cm
A sprinkler sprays water in a circle with a radius of 4 m. What area does it cover? Use π = 3.14.
A = πr²
A = 3.14 × 4²
A = 3.14 × 16
A = 50.24 m²
A triangle has angles of 35° and 75°. What is the missing angle?
35° + 75° = 110°
180° - 110° = 70°
A triangle has an area of 36 cm² and a base of 9 cm. What is the height?
36 = 9 × h ÷ 2
36 × 2 = 72
72 ÷ 9 = 8 cm
Find the circumference of a circle with a diameter of 10 cm. Use π = 3.14.
C = πd
C = 3.14 × 10
C = 31.4 cm
Find the missing leg if c = 13 cm and a = 5 cm.
b² = c² - a²
b² = 13² - 5²
b² = 169 - 25
b² = 144
b = 12 cm
A ladder leans against a wall. The bottom of the ladder is 6 m from the wall, and the ladder is 10 m long. How high up the wall does it reach?
b² = c² - a²
b² = 10² - 6²
b² = 100 - 36
b² = 64
b = 8 m