Question

Three angles of quadrilateral are respectively equal to ${110}^{\circ },{50}^{\circ },{40}^{\circ }$. Find its fourth angle.

Answer 1

Sum of angles of quadrilateral $={360}^{\circ }$

${110}^{\circ }+{50}^{\circ }+{40}^{\circ }+x={360}^{\circ }$

$x={360}^{\circ }-{200}^{\circ }={160}^{\circ }$