Area of a Triangle
Learn how to calculate the area of triangles using base and height. Let's get started! 🚀
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Flashcards
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%20Regular%20triangles%20Example.webp)
%20Right-angled%20triangles%20Example.webp)
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🛎️ What is the Area of a Triangle
- The area of a triangle is given by:
- The height must be perpendicular to the base.
🛎️ Finding the Area of a Triangle
- If you know a base and its perpendicular height, you can find the area.
- Multiply base × height, then divide by 2.
🛎️ Area of a Right-Angled Triangle
- In a right-angled triangle, the two perpendicular sides are called the legs.
- To find the area, multiply the legs, then divide by 2.
🛎️ Finding the Height from the Area
- Use the same formula:
- Substitute the known values and solve for the missing height.
Practice Questions
Test your understanding
The base of a triangle is 10 cm, and the corresponding height is 5 cm. What is the area?
Correct! 🎉 +10 pointsNot quite right
Use the formula: area = 1/2 × base × height. So, 1/2 × 10 × 5 = 25 cm².
The base of a triangle is 12 cm, and the height is 4 cm. What is the area?
Correct! 🎉 +10 pointsNot quite right
Area = 1/2 × 12 × 4 = 24 cm².
Find the area of the triangle with a base of 12 cm and a height of 5 cm.
Correct! 🎉 +20 pointsNot quite right
Area = 1/2 × 12 × 5 = 30 cm².
Find the area of the right-angled triangle with perpendicular sides 8 cm and 6 cm.
Correct! 🎉 +20 pointsNot quite right
In a right-angled triangle, the two perpendicular sides are the base and height. Area = 1/2 × 8 × 6 = 24 cm².
Find the area of the triangle with a base of 15 cm and a perpendicular height of 8 cm.
Correct! 🎉 +20 pointsNot quite right
Even if the height is outside the triangle, it is still valid. Area = 1/2 × 15 × 8 = 60 cm².
A triangle has perpendicular sides of 12 cm and 16 cm. The base is 20 cm. What is the height relative to the base?
Correct! 🎉 +30 pointsNot quite right
First find the area using the perpendicular sides: area = 1/2 × 12 × 16 = 96 cm². Then use 1/2 × 20 × h = 96. Solving gives h = 9.6 cm.
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