How to extend line of best fit to find x intercept ?

This is my plot, and I simply wish to find where the line of best fit meets with the x axis.

x=[0.200 0.100 0.067 0.050 0.040 0.033 0.025];
y=[0.214 0.158 0.130 0.125 0.136 0.115 0.107];
axis([0 0.025 0 0.025]);
plot(x,y,'x');
hold on
title('lineweaver-burk plot');
xlabel('1/S');
ylabel('1/Vo ');
figure(2)
scatter(x,y);
%Plotting the line of best fit 
p=polyfit(x,y,1);
x1=linspace(min(x), max(x), 100);
y1=polyval(p,x1);
plot(x1,y1,'r-', 'LineWidth',3);
hold off

Any help would be appreciated! (I'm a beginner!)

Answer 1

[Matt J]

roots(p)

[Yash Mantri]

Oh thanks! That works :)

Quick follow-up question :What if I have to find the Y intercept in such a case?

[Matt J]

Oh thanks! That works :)

You're welcome. Please Accept-click the answer to signify that it addressed your question.

Quick follow-up question :What if I have to find the Y intercept in such a case?

That would be

polyval(p,0)

or

p(2)