how can i see the linear variation in the graph?

the plot command does plot the graph specificaly. it just shows the x and y axis values

Answer 1

[Stephan]

H = [ 1:2:11];
L = 0.0065; %K/m 
T0= 288.15; % till 11 km 
T = T0 - L.*H; %K
plot(T,H,'-o')