[Note:
Your entire problem appeared on the site only as 

"Two angles"

That's because you can't use the 'less than' symbol " < " to indicate
an angle unless you skip a space immediately after it. Otherwise the
computer takes the " < " symbol to be the beginning of an HTML tag.)



When two angles are 'complementary' the sum of their measures is 90°.
Therefore:

(3x+2)° + (x+8)° = 90°

Solve that and get x = 20°

Then substitute 20° for x in 3x+2 and get 3(20°)+2 = 62° and
in x+8 and get (20°)+8 = 28°, and check that 62°+28°=90°.

(If the word had been "supplementary" instead of "complementary" 
the sum of the angles would have been 180° instead of 90°.

Edwin