Answer:
a= 180-60-55=65
we know that the angle of a flat(?) ground would be 180, so we can take away the 60 and 55 to find a.
b=180-90-65=25
the sum of interior angle of a triangle would be 180, now we know what a is, also the right angle is 90, now we can take away the 90 and 65 to find b.
c=25
c is 25, because two angles on both sides of a X is the same
