Question

In the figure given below, PTU is a straight line. What is the value of $x$?

• A. ${100}^o$
• B. ${110}^o$
• C. ${120}^o$
• D. ${130}^o$

Answer 1

Answer: (A)

${100}^o$

$PQRST$ is a pentagon. Therefore, sum of the internal angles of $PQRST=(5-2){180}^o={540}^o$
$\angle PTS={180}^o-{85}^o={95}^o$ (Linear pair)
$\therefore$ $x+{125}^o+{95}^o+{130}^o+{90}^o={540}^o$
$\Rightarrow$ $x+{440}^o={540}^o$
$\Rightarrow$ $x={540}^0-{440}^o={100}^o$