Question

three angles of a quadrilateral are 50°, 40° and 90°.then fourth angle is​

Answer 1

Answer:

180° (by angle sum property of quardilateral)

Answer 2

Answer:

The sum of angles of a quadrilateral is 360.

Let x = the unknown angle.

50 + 40 + 90 + x = 360.

180 + x = 360.

So x = 180.

Therefore the 4th angle is 180 degrees.