# A design is made up of four congruent right triangles as shown in Fig. 9.63. Find the area of the shaded portion.

**Solution:**

Given, a design is made up of four congruent right triangles.

We have to find the area of the shaded region.

Consider the __square__ ABCD,

Side of square = 30 + 10 = 40 cm

__Area of square__ = (side)²

= (40)²

= 1600 cm²

Considering one right angled triangle BGH,

__Area of triangle__ = 1/2 × base × height

Area of triangle BGH = 1/2 × BH × BG

= 1/2 × 10 × 30

= 10(15)

= 150 cm²

Since the triangles are congruent,

Area of 4 triangles = 4(150)

= 600 cm²

Area of the shaded portion = area of square - area of 4 congruent triangles

= 1600 - 600

= 1000 cm²

Therefore, the area of the shaded portion is 1000 cm².

**✦ Try This: **Find the perimeter of the given figure.

**☛ Also Check: **NCERT Solutions for Class 7 Maths Chapter 11

**NCERT Exemplar Class 7 Maths Chapter 9 Problem 118**

## A design is made up of four congruent right triangles as shown in Fig. 9.63. Find the area of the shaded portion.

**Summary:**

A design is made up of four congruent right triangles as shown in Fig. 9.63. The area of the shaded portion is 1000 cm².

**☛ Related Questions:**

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