Given that ∠A and ∠B are vertical angles, we know that their measures are equal. Therefore, if \( m∠A = 22° \), it follows that:
\[ m∠B = m∠A = 22° \]
Additionally, since ∠B is complementary to ∠C, we can use the property of complementary angles which states that the sum of two complementary angles is 90 degrees:
\[ m∠B + m∠C = 90° \]
Substituting \( m∠B \) with 22° gives us:
\[ 22° + m∠C = 90° \]
To find an equation that you can use to solve for \( m∠C \), we can rearrange this equation:
\[ m∠C = 90° - 22° \]
Thus, the equation you can use to solve for \( m∠C \) is:
\[ m∠C = 90° - m∠B \]
Specifically, substituting the known measure:
\[ m∠C = 90° - 22° \]
So you have the equation:
\[ m∠C = 90° - 22° \]