Answer:
see explanation
Step-by-step explanation:
The exterior angle of a triangle is equal to the sum of the 2 opposite interior angles.
∠ ACD is an exterior angle of the triangle, thus
43 + 5x - 48 = 3x + 57 , that is
5x - 5 = 3x + 57 ( subtract 3x from both sides )
2x - 5 = 57 ( add 5 to both sides )
2x = 62 ( divide both sides by 2 )
x = 31
Thus
∠ ABC = 5x - 48 = 5(31) - 48 = 155 - 48 = 107°
∠ ACD = 3x + 57 = 3(31) + 57 = 93 + 57 = 150°
