Question

The centre of a clock is taken as origin At 4.30 pm the equation of line along minute hand is x = 0 Therefore at this instant the equation of line along the hour hand will be

• A. $x-y=0$
• B. $x+y=0$
• C. $y=\sqrt{2x}$
• D. $y=\frac{x}{\sqrt{2}}$

Answer 1

The correct option is B $x+y=0$

The centre of a clock is taken as origin. At $4:30$ pm equation of line along minute hand is $x=0$.
Therefore at this instant the equation of line along the hour hand will be
$m=-1$ ( as $\tan {135}^o=-1$ )
Therefore equation of line y=mx
or $y=-x$
$y+x=0$.