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One angle of a triangle is 45^(@) and th...

One angle of a triangle is `45^(@)` and the other two are in the ratio 2:3. find these angles.

A

`50^(@),85^(@)`

B

`54^(@),81^(@)`

C

`54^(@),70^(@)`

D

`44^(@),81^(@)`

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem, we need to find the angles of a triangle where one angle is given as \(45^\circ\) and the other two angles are in the ratio \(2:3\). ### Step-by-Step Solution: 1. **Identify the Given Information:** - One angle of the triangle (let's call it angle B) is \(45^\circ\). - The other two angles (angle A and angle C) are in the ratio \(2:3\). 2. **Express the Angles in Terms of a Variable:** - Let angle A = \(2x\) (since it corresponds to the ratio of 2). - Let angle C = \(3x\) (since it corresponds to the ratio of 3). 3. **Use the Triangle Angle Sum Property:** - The sum of the angles in a triangle is always \(180^\circ\). - Therefore, we can write the equation: \[ \text{Angle A} + \text{Angle B} + \text{Angle C} = 180^\circ \] - Substituting the known values: \[ 2x + 45^\circ + 3x = 180^\circ \] 4. **Combine Like Terms:** - Combine \(2x\) and \(3x\): \[ 5x + 45^\circ = 180^\circ \] 5. **Isolate the Variable:** - Subtract \(45^\circ\) from both sides: \[ 5x = 180^\circ - 45^\circ \] \[ 5x = 135^\circ \] 6. **Solve for \(x\):** - Divide both sides by 5: \[ x = \frac{135^\circ}{5} \] \[ x = 27^\circ \] 7. **Find the Values of Angle A and Angle C:** - Substitute \(x\) back into the expressions for angle A and angle C: - Angle A: \[ \text{Angle A} = 2x = 2 \times 27^\circ = 54^\circ \] - Angle C: \[ \text{Angle C} = 3x = 3 \times 27^\circ = 81^\circ \] 8. **Final Angles of the Triangle:** - Angle A = \(54^\circ\) - Angle B = \(45^\circ\) - Angle C = \(81^\circ\) 9. **Verification:** - To ensure the angles are correct, check if they sum to \(180^\circ\): \[ 54^\circ + 45^\circ + 81^\circ = 180^\circ \] ### Conclusion: The angles of the triangle are: - Angle A = \(54^\circ\) - Angle B = \(45^\circ\) - Angle C = \(81^\circ\)
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Knowledge Check

  • One angle of a right-angled triangle is 38^(@) . Find the other angle.

    A
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    B
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    C
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    D
    `42^(@)`
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