If two angles are complementary, their measures add up to 90 degrees. Given that \( m∠2 = 26^\circ \), you can express the relationship between the angles with the following equation:
\[ m∠1 + m∠2 = 90^\circ \]
Substituting \( m∠2 \) into the equation gives:
\[ m∠1 + 26^\circ = 90^\circ \]
This is the equation you can use to solve for \( m∠1 \).