We know the measures of two complementary angles. The measure of ∠ E is (x - 10)^(∘) and the measure of ∠ F is (x + 2)^(∘).
Since the angles E and F are complementary, we know that the sum of their measures should equal 90^(∘). We can solve for x by creating an equation using the expressions for the two smaller angles and their sum.