How can I add a horizontal dashed line with a text description above it to a specific coordinate?

Dear all, I would like to inquire about the process of adding a horizontal dashed line with a text description above it to a specific coordinate on a graph, as demonstrated in Figure 1. I would appreciate it if you could guide me on how to do this. Thank you for your time and consideration.

Figure 1.

Answer 1

[Star Strider]

Perhaps this —

t = linspace(0, 5);
k = 0.75;
y = 5*(1-exp(-k*t));

yval = 3;
tval = interp1(y, t, yval);

figure
plot(t, y)
hold on
plot([min(xlim) tval], [1 1]*yval, '--r', 'LineWidth',2)
plot(tval, yval, 'or', 'MarkerFaceColor','g', 'MarkerSize',8)
hold off
text(tval/2, yval, 'text', 'Horiz','center', 'Vert','bottom')

.

[Navid]

Thank you for your time and consideration.

[Star Strider]

As always, my pleasure!