Question

The locus of the point which is at a distance $5$ units from $x-$axis is

• A. $y^2+25=0$
• B. $y^2-25=0$
• C. $y+25=0$
• D. $y-25=0$

Answer 1

The correct option is B $y^2-25=0$

Let our point be $(x,y)$

Distance of any point from $x$-axis $=$ magnitude of its y coordinate

From the question we have,

Distance of any point from $x$-axis $=5$

Which implies that

$|y|=5$

Now squaring each side we get

$y^2=25$ which can be re-written as

$y^2-25=0$