Question

Find a formula for the shortest distance from a point (a,b,c) to the x-axis. distance

Answer 1

For point P(a,b,c)
a is along the x-axis, so does not change the distance from the x-axis.
b and c are both the distance from the x-axis.
Therefore, by the Pythagoras theorem, the
distance from P to the x-axis = $\sqrt{b^2+c^2}$