Congruent Triangles std8 Page-35.4 EM

Isosceles Triangle | Find Area | Integer Values Using Pythagorean Triples

🔷 Isosceles Triangle ABC (AB = AC) AB = AC = 5 cm Base BC = 6 cm 📐 Height from A to BC (h) is perpendicular

✍️ Step-by-Step: Calculate the Area

1 Identify the base

In triangle ABC, which side is the base?

2 Base length

Base BC = 6 cm. What is half of the base?

3 Identify the equal sides

Which sides are equal in isosceles triangle ABC?

4 Height formula using Pythagorean theorem

In right triangle ABD (where D is midpoint of BC), which sides are used?

5 Calculate half of base

Half of base = BD = DC = 3 cm. AB = 5 cm. Find AD (height).

6 Apply Pythagorean theorem

AB² = AD² + BD². So AD = √(AB² - BD²) = √(25 - 9) = √(16) = ?

7 Height of the triangle

The height (altitude) from A to BC is:

8 Area formula

Area of a triangle = ?

9 Calculate the area

Area = ½ × base × height = ½ × 6 × 4 = ? cm²

10 Final Answer

The area of the isosceles triangle is:

📐 Isosceles Triangle | Find the Area (Integer Values)