documentclass[12pt,a4paper]{article}
usepackage{amsmath,amssymb}
usepackage{pstricks} % required package
usepackage{pst-node,pst-func,pst-plot,pst-eucl,pstricks-add,pst-node,multido}
usepackage{graphicx}
usepackage[margin=2.1cm]{geometry}
usepackage{auto-pst-pdf}
begin{pspicture}[algebraic,linestyle=curve](-2,-6)(6,6)
psaxes{->}(0,0)(-2,-4)(5.5,4)[$x$,0][$y$,90]
psclip{%
    psplot[linestyle=none]{0}{6.5}{x*(3-x)/2}}
psplot[linecolor=blue,fillstyle=vlines]{.5}{5}{x*(x-6)+6}
endpsclip
psplot{0}{4.5}{x*(3-x)/2}}
psplot[linecolor=blue]{.5}{5}{x*(x-6)+6}
rput[bl](1.8,1.2){$y=dfrac{-x^2+3x}{2}$}
rput[t](2,-3.1){$y=x^2-6x+6$}

begin{pspicture}[algebraic,linestyle=curve](-2,-6)(6,6)
psaxes{->}(0,0)(-2,-4)(5.5,4)[$x$,0][$y$,90]
psclip{%
    psplot[linecolor=blue,]{-1}{5}{-1*x+2}}
    psplot[fillstyle=hlines]{.5}{5}{x*(x-6)+6}
endpsclip
psplot[linewidth=1.5pt]{.5}{5}{x*(x-6)+6}
rput[bl](1.5,1){$y=-x+2$}
rput[t](2,-3.1){$y=x^2-6x+6$}
end{pspicture}