Answer:
x = 11
Step-by-step explanation:
The sum of the 3 angles in a triangle = 180°
sum the 3 angles and equate to 180
5x + 4 + 6x - 3 + 4x + 14 = 180 ← collect like terms on left side
15x + 15 = 180 ( subtract 15 from both sides )
15x = 165 ( divide both sides by 15 )
x = 11
