# Why does my plot not appear?

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Aric Rozario on 23 Oct 2020
Commented: Walter Roberson on 23 Oct 2020
Vmax = 354*10^(-6);
Km = 1.5*10^(-3);
S = .0000005:.0000005:.000030;
v = Vmax*S/(Km + S);
plot(S,v);
This is my code and it shows no errors but it does not appear on the figure tab. I am a beginner and I do not know how to correct this.

Rafael Hernandez-Walls on 23 Oct 2020
Vmax = 354*10^(-6);
Km = 1.5*10^(-3);
S = .0000005:.0000005:.000030;
v = Vmax*S./(Km + S);
plot(S,v);

Aric Rozario on 23 Oct 2020
Where did I go wrong and how come my plot is linear and not a curved graph?
Aric Rozario on 23 Oct 2020
Vmax = 354*10^(-6);
Km = 1.5*10^(-3);
S = .0000005:.0000005:.000030;
v = Vmax*S./(Km + S);
plot(S,v,1./S,1./v);
grid on;
title('Rate of Enzyme Rxn ([S] vs. v)')
xlabel('[S] (mM)')
ylabel('v (umol/sec)')
legend({'[S] vs. v','1/[S] vs. 1/v'},'Location','southwest')
ax = gca;
ax.FontSize = 13;
Also, how come now only one of my plots appear?
Walter Roberson on 23 Oct 2020
You used the / operator instead of the ./ operator. A/B is approximately the same as A*pinv(B) -- an algebraic matrix operator, not an element-by-element operator.
The S values you are adding to Km are vary small, so Km+S is the same as Km alone, to within the resolution that you are plotting at.