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If the three angles of a triangle are (x+15),

- Isosceles
- Equilateral
- Right triangle
- Scalene

Asked by RohitKumar on 22nd August 2015 in Maths.

1 Answers

Professor

**Answer: (2) Equilateral**

**Explanation:- **As we know that, the sum of the angles of a triangle always is 180 degree.

Then,

(x + 15) + (6 x/5 + 6) + (2 x/3 + 30) = 180

x + 15 + 6 x /5 + 6 + 2 x/3 + 30 = 180

x + 6 x/5 + 2 x/3 = 180 – 30 – 15 – 6

(15 x + 18 x + 10 x )/15 = 129

43 x = 129 x 15

x = 129 x 15/43

x = 3 x 15

x = 45 degree

Then, the value of x + 15 = 45 + 15 = 60 degree

The value of 6 x / 5 + 6 = 6 x 45/5 + 6

= 6 x 9 + 6 = 54 + 6 = 60 degree

And third angle = 180 – (60 + 60)

= 180 – 120 = 60 degree

Then, the triangle is equilateral .

Hence, the answer is (2) Equilateral.

Answered by Anurag Mishra on 22nd August 2015..