Answer:
x = 20
Step-by-step explanation:
The sum of the 3 angles in a triangle = 180°
Sum the 3 given angles and equate to 180
3x + 1 + x + 14 + 4x + 5 = 180, that is
8x + 20 = 180 ( subtract 20 from both sides )
8x = 160 ( divide both sides by 8 )
x = 20
