Question

Show that each of the four angles of rectangle is a right angle ​

Answer 1

Answer:

the sum interior angles of a quadrilateral =360

as a rectangle has 4 sides the measure of a angle = 360÷4

=90°

hence proved measure of a side=90°

hope this helps.!!

Answer 2

Answer:

Given:

a rectangle ABCD

to prove

angle A= angle B= angle C= angle D=90°

proof:

we know that, rectangle is a parallelogram where one angle is 90°

hence let's assume

angle A =90°

now,

AD || BC.

& AB is a transversal

( opposite sides of parallelogram are parallel)

so, angle A + angle B=180°

( interior angles on the same sides of transversal are supplementary)

angle B + 90° =180° (angle A= 90°)

angle B= 180°-90°

angle B =90°

now we know that

opposite angle of parallelogram are equal

since, angle C = angle A and angle D=angle B

since, angle C =90° and angle D=90°

so each of the angle of a rectangle in right angle are equal

hence proved