The length of the sides of a triangle are in the ratio 4 : 5 : 3 and its perimeter is 96 c m . Find its area.

Given, Length sides of triangle = 4 : 5 : 3 Therefore, a = 4 x , b = 5 x , c = 3 x 4 x + 5 x + 3 x = 96 x = 96 12 = 8 c m Thus, a = 4 x = 4 8 = 32 c m b = 5 x = 5 8 = 40 c m c = 3 x = 3 8 = 24 c m s = a + b + c 2 = 32 + 40 + 24 2 = 96 2 = 48 c m Area of triangle = s ( s - a ) ( s - b ) ( s - c ) = 48 48 - 32 48 - 40 48 - 24 = 48 × 16 × 8 × 24 = 147456 = 384 c m 2 Hence, the area of the triangle is 384 c m 2 .

E M B I B E

Concise Mathematics Middle School Class 8>Chapter 20 - Area of a Trapezium and a Polygon>EXERCISE 20(A)

R K Bansal Solutions for Chapter: Area of a Trapezium and a Polygon, Exercise 1: EXERCISE 20(A)

Author:R K Bansal

R K Bansal Mathematics Solutions for Exercise - R K Bansal Solutions for Chapter: Area of a Trapezium and a Polygon, Exercise 1: EXERCISE 20(A)

Attempt the practice questions on Chapter 20: Area of a Trapezium and a Polygon, Exercise 1: EXERCISE 20(A) with hints and solutions to strengthen your understanding. Concise Mathematics Middle School Class 8 solutions are prepared by Experienced Embibe Experts.

Questions from R K Bansal Solutions for Chapter: Area of a Trapezium and a Polygon, Exercise 1: EXERCISE 20(A) with Hints & Solutions

HARD

8th ICSE

IMPORTANT

Concise Mathematics Middle School Class 8>Chapter 20 - Area of a Trapezium and a Polygon>EXERCISE 20(A)>Q 9

A find is in the shape of a quadrilateral $A B C D$ in which side $A B = 18 m$ , side $A D = 24 m$ , side $B C = 40 m$ , $D C = 50 m$ and angle $A = 90 °$ . Find the area of the field.

Question Image

HARD

8th ICSE

IMPORTANT

Concise Mathematics Middle School Class 8>Chapter 20 - Area of a Trapezium and a Polygon>EXERCISE 20(A)>Q 10

The length of the sides of a triangle are in the ratio $∆ B C D$ and its perimeter is $96 c m$ . Find its area.

HARD

8th ICSE

IMPORTANT

Concise Mathematics Middle School Class 8>Chapter 20 - Area of a Trapezium and a Polygon>EXERCISE 20(A)>Q 11

One of the equal sides of an isosceles triangle is $13 c m$ and its perimeter is $50 c m$ . Find the area of triangle.

HARD

8th ICSE

IMPORTANT

Concise Mathematics Middle School Class 8>Chapter 20 - Area of a Trapezium and a Polygon>EXERCISE 20(A)>Q 12

The altitude and the base of a triangular field are in the ratio $6 : 5$ . If its cost is $₹ 49, 57, 200$ at the rate of $₹ 36, 720$ per hectare and $1$ hectare $= 10, 000 m^{2}$ . Find (in metres) dimensions of the field.