Question

find the measures of the numbered angles in the isosceles trapezoid. m∠1 = 55°, m∠2 = 125°, m∠3 = □°

Explanation:

Step1: Use property of isosceles trapezoid

In an isosceles trapezoid, base - angles are equal.

Step2: Identify angle relationships

Since $\angle1$ and the given $55^{\circ}$ angle are base - angles, $\angle3$ and $\angle2$ are also base - angles. Also, adjacent angles along a non - parallel side of a trapezoid are supplementary.
We know that $\angle1 = 55^{\circ}$ and $\angle2=125^{\circ}$. Because $\angle2$ and $\angle3$ are base - angles of the isosceles trapezoid, they are equal.

Answer:

$125$