The sum of the angle measures of any triangle is 180 degrees. Angle 2 is twice the measure of angle 1. Angle 3 is 15 degrees less than the measure of angle 2. What is the measure of each angle?

39°, 78°, 63°

Step-by-step explanation:

let ∠ 1 = x, then

∠ 2 = 2x ( twice the measure of ∠ 1 )

∠ 3 = 2x - 15 ( 15° less than ∠ 2 )

Sum the 3 angles and equate to 180

x + 2x + 2x - 15 = 180, that is

5x - 15 = 180 ( add 15 to both sides )

5x = 195 ( divide both sides by 5 )

x = 39

Thus

∠ 1 = 39°

∠ 2 = 2 × 39° = 78°

∠ 3 = 78° - 15 = 63°