We want to find the value of x. Examining the diagram, we notice that the angles form a linear pair. Recall the Linear Pair Theorem.
Linear Pair Theorem
If two angles form a linear pair, then they are supplementary angles.
Since the angles are supplementary, we know that the sum of their measures should equal 180^(∘). With this information, we can write an equation by adding the smaller angle's measure, setting their sum equal to 180^(∘), and solving for x^(∘).
