The domain of a function is the set of input values, x x , for which a function is defined. ... We also know we can't take the square root of a negative number. ... are not in the domain, you must find the values where the function is not defined. ... value has one and only one range value as a result, but not necessarily vice versa.

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.