Finding intersection points of two lines?

Do you know how to get those intersections btw two lines? the actual intersection points.. I have x from 0 to 40 and y from 0 to 100 which are divided 3600 points.

figure, plot(Stroke,Force);

hold on

coe = polyfit([3.8780 6.8480], [20.0531 60],1);

a = coe(1); b = coe(2);

y = a*Stroke + b;

y1 = a*Stroke +b + 0.02*b;

grid, plot(Stroke,y1)

ylim([0 100])

this is my code so far, Could you help me, anyone asap?

Answer 1

[Image Analyst]

Compute the absolute differences

absDiff = abs(Force - y1);

Then sort and find out the 3 smallest distances

[sortedDiffs, indexes] = sort(absDiff);

Then look at indexes(1:3)

crossingStrokes = Stroke(indexes(1:3));