Angle measures of a parallelogram

In any polygon, the interior angles have certain properties. Opposite angels are congruent (D = B). A parallelogram however has some additional properties.

As you drag any vertex in the parallelogram above, note that the opposite angles are congruent (equal in measure ). Angles a and b add up to 180°, so they are supplementary angles.

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Includes full solutions and score reporting. Using the above rhombus, find the measurement of angle. Possible : Correct answer: Explanation: A rhombus must have equivalent opposite interior angles. Additionally, the sum of all four interior angles must equal degrees. Identify properties, including angle measurements , of quadrilaterals.

As with triangles and other polygons, quadrilaterals have special properties and can be classified by characteristics of their angles and sides. Parallelograopposite sides and angles are congruent, Proof - Duration: 2:26. For more practice and to create math worksheets, visit Davitily Math. Step 1: Add together the measures of the known angles.

Step 2: Subtract the sum from 360° to determine what remains for the fourth angle . The measure of the unknown angle is 145°. The great thing about parallelograms is that the two . There are two components to solving this geometry puzzle. Secon one must know that the other two interior angles . For AAA (or just AA, because you only need two of the angles ) it . You can put this solution on YOUR website! These are adjacent angles , right? So if both of these are congruent, if their measures equal each other, they both have to be equal to 90.

So if adjacent angles are congruent in the parallelogram , then these angles are 90. And if these angles are 9 those are going to be 90 . But what happens when we have polygons with more than three sides . If you have colored pencils, outline the parallelogram in another color. Can you conclude anything about parallelograms , other than opposite sides are parallel?

If we extend the sides of the parallelogram in both directions, we now have two parallel lines cut by two parallel transversals. Measure each and then measure the .