Question

rectangle abcd has four right angles.

1. what is the sum of its angle measures? 360°
2. move vertex a to a different location. which vertex angle remains unchanged? c
3. what is the sum of the angle measures of the quadrilateral?

m∠a = 90°
m∠b = 90°
m∠c = 90°
m∠d = 90°

Explanation:

Step1: Recall angle - sum formula for polygons

The sum of interior - angle measures of a polygon with \(n\) sides is given by \((n - 2)\times180^{\circ}\).

Step2: Identify \(n\) for a quadrilateral

A quadrilateral has \(n = 4\) sides.

Step3: Calculate the sum

Substitute \(n = 4\) into the formula: \((4 - 2)\times180^{\circ}=2\times180^{\circ}=360^{\circ}\).

Answer:

\(360^{\circ}\)