reset
set border
set xtics 2
set ytics 500
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 [-20:20]
set yrange [-500:5000]
set samples 1000
set key on
g(x)=4*x**2-8*x-12
f(x)=-19*x**2+5*x+4671
h(x)=f(x)/g(x)
# 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 f(x) ls 1,g(x) ls 2