A side of the triangle below has been extended to form an exterior angle of 127°. Find the value of x

1 answer

Since the exterior angle of a triangle is equal to the sum of its adjacent interior angles, we can subtract the given 127° from 180° to find the measure of the corresponding interior angle:

180° - 127° = 53°

This angle is opposite to the side of length x, so we can use the sine ratio to find x:

sin 53° = x / (10 + x)

Cross-multiplying, we get:

x = (10 + x) sin 53°

Expanding:

x = 10 sin 53° + x sin 53°

Subtracting x sin 53° from both sides:

x - x sin 53° = 10 sin 53°

Factoring out x:

x (1 - sin 53°) = 10 sin 53°

Dividing both sides by (1 - sin 53°):

x = 10 sin 53° / (1 - sin 53°)

Using a calculator:

x ≈ 17.6

Therefore, the value of x is approximately 17.6 units.