reset
set border
set xtics 1
set ytics 1
set xzeroaxis lt 9 lw 5
set yzeroaxis lt 9 lw 5
set style line 1 lt 1 lw 4
set style line 2 lt 3 lw 5
set style line 3 lt 10 lw 6
set style line 4 lt 12 lw 3
set style line 5 lt 9 lw 1
set grid ls 5
show grid
set xrange [-12.5:12.5]
set yrange [-5:25]
set samples 1000
set key on
f(x)=0.1547*x**2
# j(x)=(x**2-9)/(x+2)
# k(x)=(x**2-9)/(x**4-8*x**2+16)
# i(x)=4*x**2+40*x+84
plot f(x) ls 1
# plot f(x) ls 1,g(x) ls 2, h(x) ls 3, i(x) ls 4 
# plot h(x) ls 1,j(x) ls 2, k(x) ls 3