If IJ=16 and JK=9, what is the length of HK⎯⎯⎯⎯⎯⎯?

If m∠abc = 70°, what is m∠abd? justify your reasoning.  using the addition property of equality, 40 + 70 = 110, so m∠abd = 110°.  using the subtraction property of equality, 70 − 30 = 40, so m∠abd = 30°.  using the angle addition postulate, 40 + m∠abd = 70. so, m∠abd = 30° using the subtraction property of equality.  using the angle addition postulate, 40 + 70 = m∠abd. so, m∠abd = 110° using the addition property of equality.

How do i find the missing angle measure in a polygon

Gabrielle's age is two times mikhail's age. the sum of their ages is 84. what is mikhail's age?