[size=150][size=200][size=100]Replace the right hand sides of [math]x_1\left(t\right)[/math], [math]y_1\left(t\right)[/math], [math]x_2\left(t\right)[/math], and [math]y_2\left(t\right)[/math]so that [math]P_1[/math] moves left to right along the line faster than [math]P_2[/math].[/size][/size][/size]