Question

In the given figure, $x={30}^o$. Then, the value of $(6y-3x)$ is ____.

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

Answer 1

The correct option is B ${150}^o$

Given that $x={30}^o$, we have $2x={60}^o$.

Also, $2x+3y={180}^o$ [linear pair]

Replacing $x$ in the above equation,

${60}^o+3y={180}^o\Rightarrow 3y={120}^o\Rightarrow y={40}^o$

Thus,

$6y-3x=6\left({40}^o\right)-3\left({30}^o\right)=240°-90°={150}^o$