# 15 Challenging Geometry Problems and Their Step-by-Step Solutions

- Author: Noreen Niazi
- Last Updated on: August 22, 2023

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Toggle**Introduction to Geometry Problems**

The area of mathematics known as geometry is concerned with the study of the positions, dimensions, and shapes of objects.Geometry has applications in various fields, such as engineering, architecture, and physics. Geometry problems are among the most challenging and exciting problems in mathematics. Understanding and mastering geometry problems is essential for anyone who wants to pursue a career in any field requiring a good understanding of geometry.

## Importance of Practicing Geometry Problems

Practicing geometry problems is essential for anyone who wants to master geometry. Geometry problems require a good understanding of the concepts, formulas, and theorems. By practicing geometry problems, you will develop a deep understanding of the concepts and the formulas.

You will also be able to identify the issues and the strategies to solve them. Practicing geometry problems will also help you to improve your problem-solving skills, which will be helpful in other areas of your life.

## Types of Geometry Problems

There are several types of geometry problems. Some of the common types of geometry problems include:

**Congruence problems:**These problems involve proving that two or more shapes are congruent.**Similarity problems:**These problems involve proving that two or more shapes are similar.**Area and perimeter problems:**These problems involve finding the area and perimeter of various shapes.**Volume and surface area problems:**These problems involve finding the volume and surface area of various shapes.**Coordinate geometry problems:**These problems involve finding the coordinates of various points on a graph.

## Strategies for Solving Geometry Problems

To solve geometry problems, you must understand the concepts, formulas, and theorems well. You also need to have a systematic approach to solving problems. Some of the strategies for solving geometry problems include:

**Read the problem carefully:**You must read the situation carefully and understand what is required.**Draw a diagram:**You need to draw a diagram representing the problem. This will help you to visualize the problem and identify the relationships between the shapes.**Identify the type of problem:**You need to identify the problem type and the applicable formulas and theorems.**Solve the problem step by step:**You need to solve the problem step by step, showing all your work.**Check your answer:**You must check it to ensure it is correct.

## Common Geometry Formulas and Theorems

To solve geometry problems, you must understand the standard formulas and theorems well. Some of the common procedures and theorems include:

**Area of a square:**side × side.**Pythagoras theorem:**a² + b² = c², where a and b are the lengths of the two sides of a right-angled triangle, and c is the hypotenuse length.**Area of a rectangle:**length × breadth.**Circumference of a circle:**2 × π × radius.**Area of a triangle:**½ × base × height.**Congruent triangles theorem:**Triangles are congruent if they have the same shape and size.**Area of a circle:**π × radius².**Similar triangles theorem:**Triangles are similar if they have the same shape but different sizes.

## 15 Challenging Geometry Problems and Their Step-by-Step Solutions

### Problem 1: Lets the length of three sides of triangle be 3 cm, 4 cm, and 5 cm. Calculate the area of a right-angled triangle.

Solution:

Using the Pythagoras theorem:

$$a² + b² = c²$$

where a = 3 cm, b = 4 cm, and c = 5 cm.

$$3² + 4² = 5²$$

$$9 + 16 = 25$$

Therefore, $$c² = 25$$, and $$c = √25 = 5 cm$$.

- The area of the triangle = $$½ × \text{base} × \text{height}$$

$$= ½ × 3 cm × 4 cm $$

$$= 6 cm².$$

### Problem 2:If the length of each side of an equilateral triangle is 10 cm then calculate its perimeter.

Solution:

As the perimeter of an equilateral triangle = $$3 × side length.$$

- Therefore, the perimeter of the triangle $$= 3 × 10 cm = 30 cm.$$

### Problem 3: If cylinder has 4cm radius and 10 cm height then what is the volume of a cylinder.

Solution:

The volume of a cylinder = $$π × radius² × height.$$

- Therefore, the volume of the cylinder $$= π × 4² × 10 cm = 160π cm³$$.

### Problem 4: If radius of a circle is given by 5cm and central angle 60° then what is the area of sector of a circle.

Solution:

The area of a sector of a circle $$= (central angle ÷ 360°) × π × radius².$$

- Therefore, the area of the sector $$= (60° ÷ 360°) × π × 5² c = 4.36 cm².$$

### Problem 5: Find the hypotenuse of right-angled triangle, if its other two sides are of 8 cm and 15 cm.

Solution:

Using the **Pythagoras theorem**:

$$a² + b² = c²$$

Where **a = 8 cm, b = 15 cm**, and c is the hypotenuse length.

$$8² + 15² = c²$$

$$64 + 225 = c²$$

- Therefore, $$c² = 289,$$ and $$c = √289 = 17 cm.$$

### Problem 6: If two parallel sides of trapezium are of length 5 cm and 10 cm and height 8 cm. Calculate the area of a trapezium.

Solution:

The area of a trapezium = $$½ × (sum of parallel sides) × height.$$

- Therefore, the area of the trapezium $$= ½ × (5 cm + 10 cm) × 8 cm = 60 cm².$$

### Problem 7: Radius and height of cone is given by 6cm and 12 cm respectively. Calculate its volume.

Solution:

The volume of a cone $$= ⅓ × π × radius² × height.$$

- Therefore, the volume of the cone $$= ⅓ × π × 6² × 12 cm³ = 452.39 cm³.$$

### Problem 8:What is the length of side of square if its area is 64 cm².

Solution:

The area of a square $$= side × side.$$

- Therefore, $$side = √64 cm = 8 cm.$$

### Problem 9: If length rectangle is 10cm and breadth is 6cm. Calculate its diagonal.

Solution:

Using the Pythagoras theorem:

$$a² + b² = c²$$

Where $$a = 10 cm$$, $$b = 6 cm$$, and c is the diagonal length.

$$10² + 6² = c²$$

$$100 + 36 = c²$$

- Therefore, $$c² = 136,$$ and $$c = √136 cm = 11.66 cm.$$

### Problem 10: If one side of regular hexagon is of 8cm then what is the area of a regular hexagon.

Solution:

The area of a regular hexagon $$= 6 × (side length)² × (√3 ÷ 4).$$

- Therefore, the area of the hexagon $$= 6 × 8² × (√3 ÷ 4) cm² = 96√3 cm².$$

### Problem 11: If radius of sphere is 7 cm, then what is its volume.

Solution:

The volume of a sphere = $$⅔ × π × radius³.$$

- Therefore, the volume of the sphere $$= ⅔ × π × 7³ cm³ = 1436.76 cm³.$$

### Problem 12: Find the hypotenuse length of a right-angled triangle with sides of 6 cm and 8 cm.

Solution:

Using the Pythagoras theorem:

$$a² + b² = c²$$

Where a = 6 cm, b = 8 cm, and c is the hypotenuse length.

$$6² + 8² = c²$$

$$36 + 64 = c²$$

Therefore, $$c² = 100,$$ and $$c = √100 cm = 10 cm.$$

### Problem 13: Find the area of a rhombus with 12 cm and 16 cm diagonals.

Solution:

The area of a rhombus = (diagonal 1 × diagonal 2) ÷ 2.

- Therefore, the area of the rhombus = (12 cm × 16 cm) ÷ 2 = 96 cm².

### Problem 14: If radius and central angle of circle is 4cm and 45° respectively then what is the length oof arc of circle.

Solution:

The length of the arc of a circle = (central angle ÷ 360°) × 2 × π × radius.

- Therefore, the length of the arc = (45° ÷ 360°) × 2 × π × 4 cm

### Problem 15: Find the length of the side of a regular octagon with the radius of the inscribed circle measuring 4 cm.

Solution:

The length of the side of a regular octagon = (radius of the inscribed circle) × √2.

Therefore, the length of the side of the octagon = 4 cm × √2

= 5.66 cm.

## Online Resources for Geometry Practice Problems

There are several online resources that you can use to practice geometry problems. Some of the popular online resources include:

**Khan Academy:**On the free online learning platform Khan Academy, you may find practise questions and video lectures on a variety of subjects, including geometry.**Mathway:**Mathway is an online tool that can solve various math problems, including geometry problems.**IXL**:IXL is a website that provides practise questions and tests on a variety of subjects, including geometry.

## 15 Challenging Geometry Problems and Their Step-by-Step Solutions

### Q: What is geometry?

A: Geometry is the branch of mathematics that studies objects’ shapes, sizes, and positions.

### Q: Why is practicing geometry problems significant?

A: Practicing geometry problems is essential for anyone who wants to master geometry. Geometry problems require a good understanding of the concepts, formulas, and theorems. By practicing geometry problems, you will develop a deep understanding of the concepts and the formulas.

### Q: What are some standard geometry formulas and theorems?

A: Some of the standard geometry formulas and theorems include the Pythagoras theorem, area of a triangle, area of a square, area of a rectangle, area of a circle, circumference of a circle, congruent triangles theorem, and similar triangles theorem.

## Conclusion

Geometry problems are among the most challenging and exciting problems in mathematics. Understanding and mastering geometry problems is essential for anyone who wants to pursue a career in any field requiring a good understanding of geometry. By practicing geometry problems and using the strategies and formulas discussed in this article, you can master geometry and improve your problem-solving skills.