Answer:
x = 20
Explanation:
Comment
If you follow the angles down, you discover 2 things
There are only 2 answers
One is the supplement of the other.
In this case, both angles can be shown to be the same. The process is accomplished by two vertically opposite angles and 2 supplements. I can't show you how this is done because there are no letters on the lines.
It turns out that 3x + 10 = 4x - 10
Solution
3x + 10 = 4x - 10 Add 10 to both sides
3x + 10 + 10 = 4x - 10 + 10 Combine
3x + 20 = 4x Subtract 3x from both sides.
3x-3x + 20 = 4x-3x Combine
20 = x