MATLAB: How to plot roots with a value used in the function

Question

I'm pretty new to matlab so sorry if this question seems trivial.

My function is y = x^2 + bx -20. Im trying to find the roots for when b = 0 to 10 then plot the roots as a function of b.

So far Ive tried to do somethin like this but the graph comes up empty.

for b = 0:10
    p = [1 b -20];
    r = roots(p)
    plot(r, b)
end

Suggestions? Any help is great thanks

Answer 1

for b = 0:10
    p = [1 b -20];
    r = roots(p);
    plot(b, r, 'k*');
    hold on
end
hold off