Question

question 8 of 25 to make sure that a given parallelogram is a rectangle, at least how many of its angles must measure 90°? a. four b. two c. one d. three

Explanation:

In a parallelogram, opposite angles are equal and adjacent angles are supplementary. If one angle of a parallelogram is 90°, then its adjacent angle is also 90° (since they are supplementary, 180 - 90 = 90), and the opposite angles to these two are also 90° due to opposite - angle equality in a parallelogram. So, if one angle is 90°, all four angles are 90°. Thus, at least one angle must measure 90° to ensure the parallelogram is a rectangle.

Answer:

C. One