Question

The second angle of a triangle is 12 less than the first angle. The third angle is two times the first. Find the

three angles.
First angle:
Second angle:
Third angle:

Answer 1

First angle: 48°

Second angle: 36°

Third angle: 96°

Explanation:

The sum of the three angles of a triangle = 180°

Let the measure of the first angle be a°

Then second angle measure = (a - 12)°

Third angle measure = 2a°

Adding up all these should equal 180°

⇒ a + a - 12 + 2a = 180

⇒ 4a - 12 = 180

⇒ 4a = 180 -+ 12

⇒ 4a = 192

⇒ a = 192/4 = 48°

Thus the first angle is 48°

Second angle = 48 - 12 = 36°

Third angle = 2 x 48 = 96°