Question

Could anyone offer a step by step on how to solve this problem?

Answer 1

`m\angle 1 = 40^\circ`

Explanation:

First, notice that the two lines are parallel as indicated by the arrow.

Therefore, by the Alternate Interior Angles Theorem:

`\angle 1\cong \angle 2`

So:

`m\angle 1 = m\angle 2`

Substitute:

`(2x+20)=(3x+10)`

Solve for x. Subtract 2x from both sides:

`20=x+10`

And subtract 10 from both sides:

`x=10`

We know that:

`m\angle 1 = 2x+20`

Substitute. Hence:

`m\angle 1 =2(10)+20=40^\circ`