Match the following reasons with the given statements of the proof. given: to prove: m ∠1 = 90° - m ∠2 1. ray st is perpendicular to ray sr. given 2. ∠rst is a right angle. substitution 3. m∠rst = 90° subtraction property of equality 4. m∠1 + m∠2 = m∠rst definition of perpendicular lines 5. m∠1 + m∠2 = 90° angle addition theorem 6. m∠1 = 90° - m∠2 definition of right angle