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In a triangle ABC, a = 13, b = 14, c = 15, then r1 = 
a) 21/2
b) 14
C) 65/8
d) 4
Correct answer is option 'A'. Can you explain this answer?
Verified Answer
In a triangle ABC, a = 13, b = 14, c = 15, then r1=a)21/2b) 14C)65/8d)...
R=∆/s
∆=√[(s)(s-a)(s-b)(s-c)]
s=(a+b+c)/2=42/2=21
∆=√[21×8×7×6] = 7×3×4 = 84
r=84/21=4
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Most Upvoted Answer
In a triangle ABC, a = 13, b = 14, c = 15, then r1=a)21/2b) 14C)65/8d)...
Given:
Triangle ABC with side lengths: a = 13, b = 14, c = 15

To Find:
The value of r1

Solution:
The radius of the inscribed circle in a triangle is given by the formula:
r1 = A / s

Where A is the area of the triangle and s is the semi-perimeter of the triangle.

Step 1: Calculate the semi-perimeter (s) of the triangle:
s = (a+b+c)/2 = (13+14+15)/2 = 21

Step 2: Calculate the area (A) of the triangle using Heron's formula:
A = sqrt(s(s-a)(s-b)(s-c))

Substituting the given values into the formula:
A = sqrt(21(21-13)(21-14)(21-15))
= sqrt(21(8)(7)(6))
= sqrt(21 * 8 * 7 * 6)
= sqrt(2^2 * 3 * 7 * 2^3 * 7 * 3)
= sqrt(2^5 * 3^2 * 7^2)
= 2^2 * 3 * 7
= 4 * 3 * 7
= 84

Step 3: Substitute the values of A and s into the formula for r1:
r1 = A / s
= 84 / 21
= 4

Therefore, the value of r1 is 4.

Answer:
The correct option is (d) 4.
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In a triangle ABC, a = 13, b = 14, c = 15, then r1=a)21/2b) 14C)65/8d)...
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In a triangle ABC, a = 13, b = 14, c = 15, then r1=a)21/2b) 14C)65/8d) 4Correct answer is option 'A'. Can you explain this answer?
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