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In a triangles ABC , angle A = x^(@) , ...

In a triangles ABC `, angle A = x^(@) , angle B = (3x - 2) ^(@) and angle C = y^(@) , " Also " ,angle C - angle B = 9^(@) ` Find all the three angles of the ` Delta ABC `.

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To find the angles of triangle ABC, we will follow these steps: ### Step 1: Set up the equations based on the given information. We know: - Angle A = x degrees - Angle B = (3x - 2) degrees - Angle C = y degrees - The sum of angles in a triangle is 180 degrees: \[ A + B + C = 180 \] Therefore, we can write: \[ x + (3x - 2) + y = 180 \quad \text{(Equation 1)} \] ### Step 2: Use the second condition provided. We are also given that: - Angle C - Angle B = 9 degrees: \[ y - (3x - 2) = 9 \quad \text{(Equation 2)} \] ### Step 3: Simplify Equation 2. From Equation 2: \[ y - 3x + 2 = 9 \] Rearranging gives: \[ y = 3x + 7 \quad \text{(Equation 3)} \] ### Step 4: Substitute Equation 3 into Equation 1. Now, substitute the value of y from Equation 3 into Equation 1: \[ x + (3x - 2) + (3x + 7) = 180 \] This simplifies to: \[ x + 3x - 2 + 3x + 7 = 180 \] Combining like terms: \[ 7x + 5 = 180 \] ### Step 5: Solve for x. Subtract 5 from both sides: \[ 7x = 175 \] Now divide by 7: \[ x = 25 \] ### Step 6: Find y using x. Now substitute x back into Equation 3 to find y: \[ y = 3(25) + 7 = 75 + 7 = 82 \] ### Step 7: Find Angle B using x. Now calculate Angle B: \[ B = 3x - 2 = 3(25) - 2 = 75 - 2 = 73 \] ### Step 8: Summarize the angles. Now we have: - Angle A = x = 25 degrees - Angle B = 73 degrees - Angle C = y = 82 degrees ### Final Answer: Thus, the angles of triangle ABC are: - Angle A = 25° - Angle B = 73° - Angle C = 82° ---
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ICSE-CHAPTERWISE REVISION (STAGE 1) -Triangles
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  6. In the given figure , BC = CE and angle 1 = angle 2. Prove that : ...

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  7. The given figure shows two isosceles triangles ABC and DBC with common...

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  8. Two sides AB and BC and median AD of triangle ABC are respectively equ...

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  9. Sides AB and BC and median AD of a triangle ABC are respectively pr...

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  10. The given figure shows PQ = PR and angle Q = angle R . Prove that D...

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  11. In the following figure , AB = BC and AD = DE. if angle B = 50^(@)...

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  12. In Delta ABC, AB = BC , AD bot BC and CE bot AB , prove that AD = CE...

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  13. Use the informations given in the following figure to find the values...

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  14. If the bisector of an angle of a triangle bisects the opposite side...

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  15. The given figure shows a Delta ABC in which AB =AC and BP =CQ . P...

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  16. Use the given figure to find the angle x.

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  17. In a triangle ABC , AB = AC and angle A = 36^(@) If the internal ...

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  18. In a triangles ABC , angle A = x^(@) , angle B = (3x - 2) ^(@) and a...

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