Question

problem 14: (first taught in lesson 30) from this given statement, select the definition, property, postulate, or theorem that justifies the prove statement. given: △abd prove: m∠a + m∠4 + m∠1 = 180

Explanation:

In a triangle, the sum of the interior - angle measures is 180 degrees. In \(\triangle ABD\), \(\angle A\), \(\angle4\), and \(\angle1\) are the interior angles of \(\triangle ABD\), so by the Triangle - Angle - Sum Theorem, \(m\angle A + m\angle4+m\angle1 = 180\).

Answer:

The Triangle - Angle - Sum Theorem