MATLAB: Can i know how to find an intersection between a line and a set of x-y datas

fitted lineintersection

So, this is a part of my codes.
p1=[1.177062971972549e+04,6.433804090025431]
x_0002=strain1([1:102]) %x-value for set of data
y_0002=p1(1)*x_0002+p1(2)-0.0002*p1(1) %a fitted straight line for the sets of data
y_data=stress1([1:102]) %y-value for set of data