The triangular side walls of a flyover have been used for advertisements. The site
earning of 5000 per mʻper year. A company hired one of its walls for 3 months.com
the walls are 122 m, 22 m and 120 m (see Fig. 12.9). The advertisements yiel
180 cm. what will
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How wil
need to divide
much rent did it pay?
the triangle. L
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Answers
Answer:The perimeter of a triangle is equal to the sum of its three sides it is denoted by 2S.
2s=(a+b+c)
s=(a+b+c)/2
Here ,s is called semi perimeter of a triangle.
The formula given by Heron about the area of a triangle is known as Heron's formula.
According to this formula area of a triangle= √s (s-a) (s-b) (s-c)
Where a, b and c are three sides of a triangle and s is a semi perimeter.
This formula can be used for any triangle to calculate its area and it is very useful when it is not possible to find the height of the triangle easily .
Heron's formula is generally used for calculating area of scalene triangle.
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Solution:
Let the sides of the triangle are a=122 m, b=22 m & c= 120 m.
Semi Perimeter of the ∆,s = (a+b+c) /2
s=(122 + 22 + 120) / 2
s= 264/2= 132m
Using heron’s formula,
Area of the wall = √s (s-a) (s-b) (s-c)
= √132(132 – 122) (132 – 22) (132 – 120)
= √132 × 10 × 110 × 12
=√11×12×10×11×10×12
=√11×11×12×12×10×10
= 11×12×10
= 1320m²
Given, earning on 1m² per year= ₹5000
Earning on 1320 m² per year=1320×5000= ₹6600000
Now, earning in 1320 m² in 12 months= ₹6600000
earning in 3 months = ₹ 6600000 ×3/12 = ₹ 1650000
Hence, the rent paid by the company for 3 months is ₹ 1650000.
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Step-by-step explanation: