Area - Examples, Exercises and Solutions

Question Types:
Area of a Circle: A shape consisting of several shapes (requiring the same formula)Area of a Circle: Calculate The Missing Side based on the formulaArea of a Deltoid: Calculation using percentagesArea of a Deltoid: Subtraction or addition to a larger shapeArea of a Deltoid: Verifying whether or not the formula is applicableArea of a Parallelogram: Using congruence and similarityArea of a Parallelogram: Using external heightArea of a Rectangle: A shape consisting of several shapes (requiring the same formula)Area of a Rectangle: Calculation using the diagonalArea of a Rectangle: Extended distributive lawArea of a Rhombus: Extended distributive lawArea of a Rhombus: Verifying whether or not the formula is applicableArea of a Trapezoid: Finding Area based off Perimeter and Vice VersaArea of a Triangle: Ascertaining whether or not there are errors in the dataArea of a Triangle: Calculating in two waysArea of a Triangle: Identifying and defining elementsArea of a Triangle: Using congruence and similarityArea of a Triangle: Worded problemsArea of a Circle: Increasing a specific element by addition of.....or multiplication by.......Area of a Rectangle: Subtraction or addition to a larger shapeArea of a Rectangle: Using Pythagoras' theoremArea of a Rhombus: Calculation using percentagesArea of a Rhombus: Finding Area based off Perimeter and Vice VersaArea of a Rhombus: Using Pythagoras' theoremArea of a Rhombus: Using variablesArea of a Trapezoid: Subtraction or addition to a larger shapeArea of a Trapezoid: Suggesting options for terms when the formula result is knownArea of a Circle: Using Pythagoras' theoremArea of a Rectangle: Using short multiplication formulasArea of a Rhombus: Using ratios for calculationArea of the Square: Increasing a specific element by addition of.....or multiplication by.......Area of a Circle: Calculating parts of the circleArea of a Circle: Using additional geometric shapesArea of a Deltoid: Using Pythagoras' theoremArea of a Parallelogram: Using Pythagoras' theoremArea of a Triangle: Subtraction or addition to a larger shapeArea of a Circle: Finding Area based off Perimeter and Vice VersaArea of a Circle: Subtraction or addition to a larger shapeArea of a Parallelogram: Calculating in two waysArea of a Rectangle: Using ratios for calculationArea of a Triangle: How many times does the shape fit inside of another shape?Area of the Square: Worded problemsArea of a Circle: Applying the formulaArea of a Parallelogram: Verifying whether or not the formula is applicableArea of a Triangle: Using Pythagoras' theoremArea of a Triangle: Using ratios for calculationArea of a Parallelogram: Using ratios for calculationArea of a Rectangle: Worded problemsArea of a Trapezoid: Using Pythagoras' theoremArea of a Trapezoid: Using ratios for calculationArea of a Deltoid: Using external heightArea of a Trapezoid: Using variablesArea of a Rhombus: Applying the formulaArea of a Rhombus: Calculate The Missing Side based on the formulaArea of a Triangle: Using additional geometric shapesArea of a Deltoid: Using ratios for calculationArea of a Rectangle: Calculate The Missing Side based on the formulaArea of a Rectangle: Using additional geometric shapesArea of a Triangle: Using variablesArea of a Deltoid: Identifying and defining elementsArea of a Parallelogram: Using additional geometric shapesArea of a Trapezoid: Using additional geometric shapesArea of a Deltoid: Using variablesArea of a Parallelogram: Using variablesArea of a Rectangle: Applying the formulaArea of the Square: True / falseArea of a Deltoid: Using additional geometric shapesArea of a Parallelogram: Finding Area based off Perimeter and Vice VersaArea of the Square: Express usingArea of a Triangle: Finding Area based off Perimeter and Vice VersaArea of the Square: Applying the formulaArea of a Deltoid: Applying the formulaArea of a Parallelogram: Calculate The Missing Side based on the formulaArea of a Rectangle: Finding Area based off Perimeter and Vice VersaArea of a Deltoid: Finding Area based off Perimeter and Vice VersaArea of a Triangle: Calculate The Missing Side based on the formulaArea of a Deltoid: Calculate The Missing Side based on the formulaArea of the Square: Calculate The Missing Side based on the formulaArea of a Trapezoid: Calculate The Missing Side based on the formulaArea of a Triangle: Applying the formulaArea of a Parallelogram: Applying the formulaArea of a Rectangle: Using variablesArea of a Trapezoid: Applying the formula

In this article, we will learn what area is, and understand how it is calculated for each shape, in the most practical and simple way there is.
Shall we start?

What is the area?

Area is the definition of the size of something. In mathematics, which is precisely what interests us now, it refers to the size of some figure.
In everyday life, you have surely heard about area in relation to the surface of an apartment, plot of land, etc.
In fact, when they ask what the surface area of your apartment is, they are asking about its size and, instead of answering with words like "big" or "small" we can calculate its area and express it with units of measure. In this way, we can compare different sizes.

Units of measurement of area

Large areas such as apartments are usually measured in meters, therefore, the unit of measurement will be m2 m^2 square meter.
On the other hand, smaller figures are generally measured in centimeters, that is, the unit of measurement for the area will be cm2 cm^2 square centimeter.
Remember:
Units of measurement for the area in cm=>cm2 cm => cm^2
Units of measurement for the area m=>m2 m=>m^2

Suggested Topics to Practice in Advance

  1. Square

Practice Area

Examples with solutions for Area

Exercise #1

What is the area of the given triangle?

555999666

Video Solution

Step-by-Step Solution

This question is a bit confusing. We need start by identifying which parts of the data are relevant to us.

Remember the formula for the area of a triangle:

A1- How to find the area of a triangleThe height is a straight line that comes out of an angle and forms a right angle with the opposite side.

In the drawing we have a height of 6.

It goes down to the opposite side whose length is 5.

And therefore, these are the data points that we will use.

We replace in the formula:

6×52=302=15 \frac{6\times5}{2}=\frac{30}{2}=15

Answer

15

Exercise #2

What is the area of the triangle in the drawing?

5557778.68.68.6

Video Solution

Step-by-Step Solution

First, we will identify the data points we need to be able to find the area of the triangle.

the formula for the area of the triangle: height*opposite side / 2

Since it is a right triangle, we know that the straight sides are actually also the heights between each other, that is, the side that measures 5 and the side that measures 7.

We multiply the legs and divide by 2

5×72=352=17.5 \frac{5\times7}{2}=\frac{35}{2}=17.5

Answer

17.5

Exercise #3

The triangle ABC is given below.
AC = 10 cm

AD = 3 cm

BC = 11.6 cm
What is the area of the triangle?

11.611.611.6101010333AAABBBCCCDDD

Video Solution

Step-by-Step Solution

The triangle we are looking at is the large triangle - ABC

The triangle is formed by three sides AB, BC, and CA.

Now let's remember what we need for the calculation of a triangular area:

(side x the height that descends from the side)/2

Therefore, the first thing we must find is a suitable height and side.

We are given the side AC, but there is no descending height, so it is not useful to us.

The side AB is not given,

And so we are left with the side BC, which is given.

From the side BC descends the height AD (the two form a 90-degree angle).

It can be argued that BC is also a height, but if we delve deeper it seems that CD can be a height in the triangle ADC,

and BD is a height in the triangle ADB (both are the sides of a right triangle, therefore they are the height and the side).

As we do not know if the triangle is isosceles or not, it is also not possible to know if CD=DB, or what their ratio is, and this theory fails.

Let's remember again the formula for triangular area and replace the data we have in the formula:

(side* the height that descends from the side)/2

Now we replace the existing data in this formula:

CB×AD2 \frac{CB\times AD}{2}

11.6×32 \frac{11.6\times3}{2}

34.82=17.4 \frac{34.8}{2}=17.4

Answer

17.4

Exercise #4

The width of a rectangle is equal to 15 cm and its length is 3 cm.

Calculate the area of the rectangle.

Video Solution

Step-by-Step Solution

To calculate the area of the rectangle, we multiply the length by the width:

15×3=45 15\times3=45

Answer

45

Exercise #5

Calculate the area of the trapezoid.

555141414666

Video Solution

Step-by-Step Solution

We use the formula (base+base) multiplied by the height and divided by 2.

Note that we are only provided with one base and it is not possible to determine the size of the other base.

Therefore, the area cannot be calculated.

Answer

Cannot be calculated.

Exercise #6

Complete the sentence:

To find the area of a right triangle, one must multiply ________________ by each other and divide by 2.

Step-by-Step Solution

To solve this problem, begin by identifying the elements involved in calculating the area of a right triangle. In a right triangle, the two sides that form the right angle are known as the legs. These legs act as the base and height of the triangle.

The formula for the area of a triangle is given by:

A=12×base×height A = \frac{1}{2} \times \text{base} \times \text{height}

In the case of a right triangle, the base and height are the two legs. Therefore, the process of finding the area involves multiplying the lengths of the two legs together and then dividing the product by 2.

Based on this analysis, the correct way to complete the sentence in the problem is:

To find the area of a right triangle, one must multiply the two legs by each other and divide by 2.

Answer

the two legs

Exercise #7

Calculate the area of the triangle below, if possible.

8.58.58.5777

Video Solution

Step-by-Step Solution

The formula to calculate the area of a triangle is:

(side * height corresponding to the side) / 2

Note that in the triangle provided to us, we have the length of the side but not the height.

That is, we do not have enough data to perform the calculation.

Answer

Cannot be calculated

Exercise #8

Look at the rectangle ABCD below.

Side AB is 6 cm long and side BC is 4 cm long.

What is the area of the rectangle?
666444AAABBBCCCDDD

Video Solution

Step-by-Step Solution

Remember that the formula for the area of a rectangle is width times height

 

We are given that the width of the rectangle is 6

and that the length of the rectangle is 4

 Therefore we calculate:

6*4=24

Answer

24 cm²

Exercise #9

Look at the rectangle ABCD below.

Side AB is 4.5 cm long and side BC is 2 cm long.

What is the area of the rectangle?
4.54.54.5222AAABBBCCCDDD

Video Solution

Step-by-Step Solution

We begin by multiplying side AB by side BC

We then substitute the given data and we obtain the following:

4.5×2=9 4.5\times2=9

Hence the area of rectangle ABCD equals 9

Answer

9 cm²

Exercise #10

Look at rectangle ABCD below.

Side AB is 10 cm long and side BC is 2.5 cm long.

What is the area of the rectangle?
1010102.52.52.5AAABBBCCCDDD

Video Solution

Step-by-Step Solution

Let's begin by multiplying side AB by side BC

If we insert the known data into the above equation we should obtain the following:

10×2.5=25 10\times2.5=25

Thus the area of rectangle ABCD equals 25.

Answer

25 cm²

Exercise #11

Given the following rectangle:

666999AAABBBDDDCCC

Find the area of the rectangle.

Video Solution

Step-by-Step Solution

We will use the formula to calculate the area of a rectangle: length times width

9×6=54 9\times6=54

Answer

54

Exercise #12

Given the following rectangle:

888444AAABBBDDDCCC

Find the area of the rectangle.

Video Solution

Step-by-Step Solution

Let's calculate the area of the rectangle by multiplying the length by the width:

4×8=32 4\times8=32

Answer

32

Exercise #13

Given the following rectangle:

222555AAABBBDDDCCC

Find the area of the rectangle.

Video Solution

Step-by-Step Solution

Let's calculate the area of the rectangle by multiplying the length by the width:

2×5=10 2\times5=10

Answer

10

Exercise #14

Given the following rectangle:

111111777AAABBBDDDCCC

Find the area of the rectangle.

Video Solution

Step-by-Step Solution

Let's calculate the area of the rectangle by multiplying the length by the width:

11×7=77 11\times7=77

Answer

77

Exercise #15

Calculate the area of the following parallelogram:

666555

Video Solution

Step-by-Step Solution

To solve the exercise, we need to remember the formula for the area of a parallelogram:

Side * Height perpendicular to the side

In the diagram, although it's not presented in the way we're familiar with, we are given the two essential pieces of information:

Side = 6

Height = 5

Let's now substitute these values into the formula and calculate to get the answer:

6 * 5 = 30

Answer

30 cm²

More Questions

Topics learned in later sections

  1. Area of a square