Question

Three angles of a quadrilateral measure ${37}^{\circ }$, ${130}^{\circ }$ and ${53}^{\circ }$. Then the fourth angle is

• A. ${40}^{\circ }$
• B. ${50}^{\circ }$
• C. ${90}^{\circ }$
• D. ${140}^{\circ }$

Answer 1

The correct option is D ${140}^{\circ }$

Let the fourth angle be $x^{\circ }$.

By angle sum property, we know that sum of interior angles of a quadrilateral is ${360}^{\circ }$.

$\Rightarrow {37}^{\circ }+{130}^{\circ }+{53}^{\circ }+x={360}^{\circ }$

$\Rightarrow x={360}^{\circ }-({37}^{\circ }+{130}^{\circ }+{53}^{\circ })$
$={360}^{\circ }-{220}^{\circ }$
$={140}^{\circ }$