Answer:
The measure of the three angles are 120°, 20° and 40°
Explanation:
Let
x ----> the measure of the first angle
y ---> the measure of the second angle (smallest angle)
z ---> the measure of the third angle
Remember that
The sum of the angles in a triangle must be equal to 180 degrees
so
----> equation A
-----> equation B
------> equation C
solve the system by substitution
substitute equation B and equation C in equation A

solve for y




Find the value of x
----
Find the value of z
---->

therefore
The measure of the three angles are 120°, 20° and 40°