The three angles in a triangle always add up to 180 degrees. If one angle in a triangle is 72 degrees and the second is 2 times the third, what are the three angles?

x+y+z=180.

y+z=180-72.

y+z=108.

y=2z.

2z+z=108.

z=108/3

=36deg.

y=2z=2*36

=72deg.