In the diagram, m∠coe = 55°. if m∠2 = 2x and m∠3 = x+10, what is the measure of angle 2?

15

30

45

60

So here is how we are going to get the measure of angle 2. 
Since given that angle COE measures 55°, we will equate m∠2 = 2x and m∠3 = x+10 with 55. So, 55 = 2x + x + 10
55 = 3x + 10
55-10 = 3x
45 = 3x << divide both sides by 3 and the result is 
15 = x
So now that we know x, we can now solve for angle 2.
m∠2 = 2x
m∠2 = 2(15)
m∠2 = 30°
I hope that this is the answer that you are looking for. 

“exterior angles of triangles. an exterior (or external) angle is the angle between one side of a triangle and the extension of an adjacent side. try this drag the orange dots on any vertex to reshape the triangle.” look to get to the answer i explained what it means and other things i hope it you .