Two complementary angles are in the ratio 4:5. Find the angles.

1.	Two complementary angles are in the ratio 4:5. Find the angles.
Answer» Consider the required angle as x° and 90° – x° According to the question it can be written as x°/ 90° – x° = 4/5 By cross multiplication we get 5x = 4 (90 – x) 5x = 360 – 4x On further calculation we get 5x + 4x = 360 9x = 360 By division x = 360/9 So we get x = 40 Therefore, the angles are 40° and 90° – x° = 90° – 40° = 50°

Answer»

Consider the required angle as x° and 90° – x°

According to the question it can be written as

x°/ 90° – x° = 4/5

By cross multiplication we get

5x = 4 (90 – x)

5x = 360 – 4x

On further calculation we get

5x + 4x = 360

9x = 360

By division

x = 360/9

So we get

x = 40

Therefore, the angles are 40° and 90° – x° = 90° – 40° = 50°

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