Solve for x in the picture below

Answer:
x = 16
Step-by-step explanation:
The sum of the exterior angles of a triangle = 360°
Sum the exterior angles and equate to 360
5x + 12 + 10x - 37 + 9x + 1 = 360 , that is
24x - 24 = 360 ( add 24 to both sides )
24x = 384 ( divide both sides by 24 )
x = 16
Answer:
x = 15
Step-by-step explanation:
The sum of angles in a triangle is 180deg.
Let's mark the measures of the internal angles as A, B and C.
We know that
A + B + C = 180deg
180deg - A + 180deg - B + 180deg - C = (9x + 1)deg + (5x + 12)deg + (10x - 37)deg
3*180deg - (A + B + C) = (24x - 24)deg
540deg - 180deg = (24x - 24)deg
360deg = (24x - 24)deg
360 = 24x - 24
384 = 24x
15 = x