Question

why angles of a rectangle is equal to 90 degree​

Answer 1

According to quadrilateral

All angles of quadrilateral is 360

so,

a = ×

b = ×

c = ×

d = ×

so a+b+c+d=360

×+×+×+×=360

4× =360

× =360÷4

× =90

so all angles of rectangle is 90