Question

19. ABCD is a parallelogram in which the two diagonals are equal
find the measure of ABC. Is the parallelogram a rectangle?​

Answer 1

Answer:

In a parallelogram if two diagonals are equal, then the parallelogram is a rectangle.So, ABCD is a rectangle.It is known that each interior angle of a rectangle is 90 degree. Since ABC is an interior angle of rectangle ABCD, so measure of angle ABC is 90 degree