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In a DeltaABC, angleA=2 angleB=3 angleC,...

In a `DeltaABC, angleA=2 angleB=3 angleC,` find each of the triangle.

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To solve the problem, we need to find the angles of triangle ABC given the relationships between the angles: \( \angle A = 2 \angle B \) and \( \angle A = 3 \angle C \). ### Step-by-Step Solution: 1. **Set Up the Relationships**: We know from the problem statement that: - \( \angle A = 2 \angle B \) (1) - \( \angle A = 3 \angle C \) (2) 2. **Express Angles in Terms of Angle B**: From equation (1), we can express \( \angle A \) in terms of \( \angle B \): \[ \angle A = 2B \] From equation (2), we can express \( \angle C \) in terms of \( \angle B \): \[ \angle C = \frac{2}{3} \angle B \] 3. **Use the Angle Sum Property**: The sum of the angles in a triangle is always 180 degrees: \[ \angle A + \angle B + \angle C = 180 \] Substituting the expressions for \( \angle A \) and \( \angle C \): \[ 2B + B + \frac{2}{3}B = 180 \] 4. **Combine Like Terms**: Combine the terms on the left side: \[ 3B + \frac{2}{3}B = 180 \] To combine \( 3B \) and \( \frac{2}{3}B \), we convert \( 3B \) into a fraction: \[ 3B = \frac{9}{3}B \] Now we can add: \[ \frac{9}{3}B + \frac{2}{3}B = \frac{11}{3}B \] So we have: \[ \frac{11}{3}B = 180 \] 5. **Solve for Angle B**: Multiply both sides by \( \frac{3}{11} \): \[ B = 180 \times \frac{3}{11} = \frac{540}{11} \] Converting this to a mixed number: \[ B = 49 \frac{1}{11} \text{ degrees} \] 6. **Find Angle A**: Using \( \angle A = 2B \): \[ A = 2 \times \frac{540}{11} = \frac{1080}{11} \] Converting to a mixed number: \[ A = 98 \frac{2}{11} \text{ degrees} \] 7. **Find Angle C**: Using \( \angle C = \frac{2}{3}B \): \[ C = \frac{2}{3} \times \frac{540}{11} = \frac{360}{11} \] Converting to a mixed number: \[ C = 32 \frac{8}{11} \text{ degrees} \] ### Final Angles: - \( \angle A = 98 \frac{2}{11} \) degrees - \( \angle B = 49 \frac{1}{11} \) degrees - \( \angle C = 32 \frac{8}{11} \) degrees
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NAGEEN PRAKASHAN ENGLISH-LINES AND ANGLES-Exercise 6 C
  1. Angles of a triangle are (3x)^(@),(2x-7) and (4x-11)^(@) . Find the me...

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  2. Prove that measure of each angle of an equilateral triangle is 60^0...

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  3. Find the x and y from the adjooining figure.

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  4. In a DeltaABC, angleA=2 angleB=3 angleC, find each of the triangle.

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  5. In DeltaABC, angleA=x+15^(@),angleB=x and angleC=2x-35^(@) find, each ...

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  6. In DeltaABC, bisectors of angleB and angleC interesct each other at po...

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  7. An angle of a triangle mesures 68^(@) and the other two angles differ ...

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  8. Find the value of x form the adjoining diagram.

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  9. In DeltaABC sides AB and C are produced to D and E respectively. Bisec...

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  10. In triangle ABC,the bisector of interior angle A and the bisector angl...

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  11. From the adjoining figure prove that angleA+angleB+angleC+angleD+angle...

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  12. The side BC of DeltaABC is product to N. bisector of angle meets BC at...

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  13. Bisectors of angles A and B of a parallelogram ABCD meet at point M. P...

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  14. Prove that bisectors of any two adjacent angles of a rhombus form a ri...

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  15. Triangle ABC is right angles at B. Internet bisectors of acute angles ...

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  16. Bisectors of angles A and D of a quadrilateral ABCD meet at P. Prove t...

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  17. In the given figure, AD is altitude and AE is bisector of angle BAC of...

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  18. In DeltaABC, angleA-angleB=16^(@) and angleC-angleA=34^(@)=34^(@) , fi...

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  19. In a right angled triangle ABC, angleB=90^(@), p is a point on BA prod...

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  20. In the adjoining figure, AB||CD. If the angleBAE=25^(@) and angleCDE=...

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