Answer:
x = 2.5
Step-by-step explanation:
In order to solve for x, we need to write an equation. This question gives us the angles of a triangle, so we can use this to write our equation. All angles of a triangle will always add to 180 degrees, therefore:
(12x+6) + 104 + 40 = 180
Now we can just take out the brackets, combine like terms and isolate and solve for x:
12x + 6 + 104 + 40 = 180
12x + 150 = 180
12x + 150 - 150 = 180 - 150
12x = 30
12x/12 = 30/12
x = 2.5
Hope this helped!