MATLAB: Plotting graph with given points

given ptgraphMATLABplotpoint

basically we always plot graph of certain function such as x = 0 : 1 : 10 y = sinx; plot(x,y,'-r^')

lets say given x = 2 y = 15 x = 3 y = 8 x = 8 y = 30 the point is random, how to plot this graph?

x=[2,3,8]; y=[15,8,30]; plot(x.y)

plot(x,y,'o') for dots

Like you can see the result is the same, but the two functions plot and scatter are different

x=[1 3 5 6];
y=10*ones(size(x));
plot(x,y,'o')