मराठी

If the Measures of Angles of a Triangle Are in the Ratio of 3 : 4 : 5, What is the Measure of the Smallest Angle of the Triangle?

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प्रश्न

If the measures of angles of a triangle are in the ratio of 3 : 4 : 5, what is the measure of the smallest angle of the triangle?

पर्याय

  • 25°

  • 30°

  • 45°

  • 60°

MCQ
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उत्तर

In the given figure, measures of the angles of ΔABC are in the ratio 3 : 4 : 5. We need to find the measure of the smallest angle of the triangle.

Let us take,

∠A = 3x

∠B = 4x

∠C = 5x

Now, applying angle sum property of the triangle in ΔABC, we get,

∠A + ∠B + ∠C = 180°

   3x + 4x + 5x = 180°

                12X = 180°

                   `x = (180°)/ 12`

                     x = 15°

Substituting the value of in ,∠A,∠Band∠C

∠A = 3(15°) = 45

∠B = 4(15V) = 60

∠C = 5(15°) = 75°

Since, the measure of ∠A is the smallest

Thus, the measure of the smallest angle of the triangle is 45°

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पाठ 11: Triangle and its Angles - Exercise 11.4 [पृष्ठ २६]

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आर.डी. शर्मा Mathematics [English] Class 9
पाठ 11 Triangle and its Angles
Exercise 11.4 | Q 15 | पृष्ठ २६

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