Answer:
all work is pictured and shown
45°
Step-by-step explanation:
The sum of the 3 angles in a triangle = 180°
Sum the 3 given angles and equate to 180, that is
3x + 4x + 5x = 180, that is
12x = 180 ( divide both sides by 12 )
x = 15
Thus
smallest angle = 3x = 3 × 15 = 45°
