The speed of a particle moving along a straight line, when it is at a distance (x) from a fixed point on the line is given by v2=108-9x2 (in CGS unit), Then

A particle executing SHM with angular frequency  ω and amplitude A has an instantaneous velocity  V=ωA2-x2 where x is the distance of the particle from a fixed point on its line of motion. The given equation can be reduced to the form, V=3232-x2.(C.G.S unit)Therefore the given equation represents SHM with amplitude 23cm