to do this problem you need to find angle adc which is a part of angle BDA. angle BDA is 90 degrees so the 2 parts must add up to 90 degrees so you set up the problem like this -2x + 144 - 3x +51 =90 then you combine like terms -5x +195 = 90 then you subtract 195 from 90 -5x = -105 then you divide -5 by -5 and -105 by -5 and get x=21 then you plug x in and get your angle measure -3(21) +51 then you get the angle measure as 114 degrees.
