posted by Bernie .
Which two triangles are similar? 48,69 Degrees, 48, 63 Degrees and 78, 63 degrees.
If two triangles are to be similar, they must have all the same angle measurements. So, if every triangle has 3 angles with the sum of 180, you can easily find the missing angle by subtracting the 2 from 180. Do that with each possibility. Then see which ones have the 3 same numbers.