Question

Three angles of a quadrilateral are 75°, 90° and 75°. Find the fourth angle.​

Answer 1

Answer:

Sum of angles of a quadrilateral is 360°

∴ fourth angle be,

⇒ 360−(75+90+75)=120°

Answer 2

Answer:

the sum of all the angles of a quadrilateral is =(n-2)*180°=(4-2=2)*180°=2*180=360°

Let the fourth angle be x

75+75+90+x=360

210+x=360°

x=360°-240°

x=120°

so the fourth side is 120°