Hi, studying to get into university. Completed 'quadratic equations' now onto the intro section of 'polynomials'.

Question is:

Prove that the Vertical Separation between the graphs 'y=x^2-4x' & 'y=-x^2+2x' is '6x-2x^2' for 0<x<3 (less than or equal to)

never heard anything about vertical separation in quadratic equations. Help is greatly appreciated!

JuanP