Area of rectangles and triangles
Calculate the area of rectangles, squares and triangles, and find the area of composite shapes made from these.
Worked examples
Finding the area of a rectangle
Straightforward
Problem
Find the area of a rectangle with length cm and width cm.
1
Write the formula for the area of a rectangle.
2
Substitute the length and width into the formula.
3
Multiply to calculate the area.
Answer
Finding the area of a triangle
Moderate
Problem
Find the area of a triangle with a base of cm and a perpendicular height of cm.
1
Write the formula for the area of a triangle.
2
Substitute the base and height into the formula.
3
Multiply to calculate the area.
Answer
Finding the area of a composite shape
Challenging
Problem
A composite shape is made of a rectangle cm long and cm tall with a triangle on top. The triangle has a base of cm and a height of cm. Find the total area.
1
Find the area of the rectangle using .
2
Find the area of the triangle using .
3
Add the two areas to find the total area.
Answer
Practise
Q1·Straightforward
A rectangle has a length of cm and a width of cm. What is its area in cm²?
Explanation
Q2·Straightforward
A square has a side length of m. What is its area in m²?
Explanation
Q3·Straightforward
A rectangle has a length of cm and a width of cm. What is its area in cm²?
Explanation
Q4·Straightforward
A rectangle has a length of m and a width of m. What is its area in m²?
Explanation
Q5·Moderate
A triangle has a base of cm and a perpendicular height of cm. What is its area in cm²?
Explanation
Q6·Moderate
A triangle has a base of m and a perpendicular height of m. What is its area in m²?
Explanation
Q7·Moderate
A triangle has a base of cm and a perpendicular height of cm. What is its area in cm²?
Explanation
Q8·Moderate
A triangle has a base of m and a perpendicular height of m. What is its area in m²?
Explanation
Q9·Challenging
A composite shape is made of a rectangle cm long and cm tall with a triangle on top. The triangle has a base of cm and a height of cm. What is the total area in cm²?
Explanation
. . Total .
Q10·Challenging
A composite shape is made of a rectangle m wide and m tall with a triangle on top. The triangle has a base of m and a height of m. What is the total area in m²?
Explanation
. . Total .
Q11·Challenging
A composite shape is made of a rectangle cm long and cm wide. A right triangle with a base of cm and a height of cm is attached to one end of the rectangle. What is the total area in cm²?
Explanation
. . Total .
Q12·Challenging
A composite shape is made of a square with side length cm and a triangle attached to one side. The triangle has a base of cm and a height of cm. What is the total area in cm²?
Explanation
. . Total .