Question

In the figure below, $x={30}^{\circ }.$ The value of $(6y–3x)$ is ___.

• A. ${60}^{\circ }$
• B. ${150}^{\circ }$
• C. ${180}^{\circ }$
• D. ${120}^{\circ }$

Answer 1

The correct option is B

${150}^{\circ }$

Given: $x={30}^{\circ }$
So, $2x={60}^{\circ }$

Also, $2x+3y={180}^{\circ }$ (linear pair)

On substituting the value of $2x$ in the above equation,

$\Rightarrow {60}^{\circ }+3y={180}^{\circ }$

$\Rightarrow 3y={120}^{\circ }$

$\Rightarrow y={40}^{\circ }$

$\therefore$ the value of $6y-3x$
$=6\times {40}^{\circ }-3\times {30}^{\circ }$
$={240}^{\circ }-{90}^{\circ }$
$={150}^{\circ }$