Draw a line on a 2D plot at a particular x and y values

I'd like to draw a line at a particular x (and corresponding y) value for a plot that looks like this:

x=linspace(0,4)
y=x.^2
plot(x,y)

If I use the data cursor, it doesn't let me place it on a particular value (in my case where x=3), so I'd like it to do that and show me the x and corresponding y coordinates somewhere on the graph. Ideally, I'd like to have a dashed line protruding from the x and y axes to this point on the graph.

Any help would be appreciated.

Thanks

Answer 1

[George Papazafeiropoulos]

x=linspace(0,4);
y=x.^2;
plot(x,y);
line([3;3],[0;9],'linestyle','--');
line([0;3],[9;9],'linestyle','--');

[Orion]

Fantastic! Thank you

[Sajid Afaque]

how do i change the color of the line ?

[ARVIND KUMAR SINGH]

x=linspace(0,4);

y=x.^2;

plot(x,y);

line([3;3],[0;9],'linestyle','--','Color','red');

line([0;3],[9;9],'linestyle','--','Color','green');

[Pulkit Rustagi]

Is it possible to label the said dashed line? is there a label field for line function?

Its not specificly mentioned in the documentation

https://www.mathworks.com/help/matlab/ref/line.html