In ΔABC,
angle BAC = 180 - 123 = 57°.......(Linear pair)
Now, We Know,
Sum of all angles in a triangle = 180°
therefore,
angle BAC + angle BCA + angle ABC = 180°
58 + 57 + x = 180°
115° + x = 180°
x = 180° - 115°
x = 65°...ans
Hope it helps you!!
