clc; clearvars; close all;

x=0:0.2:3;
y=x.^2 + 1;
plot(x,y)
pause(5)
hold on
x1=[0 3]; y1=[0 0]; x2=[0 0]; y2=[0 10];
plot(x1,y1,'-b',x2,y2,'-b')
grid on
hold off