Plotting Issue with code

Having problems with the plot of Temp vs XE,

X vs Temp

Temp vs Kc

X vs Kc

all produce plots which are expected but when XE is involved there isn't a plot produced..

Any advice?Code:

function 
%Given Data
To=325;
dH=-20000;
Cpa=20;
Cpb=20;
Kc1=1000;
R=0.001987;
dH1=-20; % dH x 10^-3

X=0:0.01:1.0;

plot(Temp,XE);

[Rena Berman]

(Answers Dev) Restored edit

Answer 1

[Bhaskar R]

MATLAB operator "/" does Solve systems of linear equations, use "./" operator instead for element wise division operation

function Plot5
%Given Data
To=325;
dH=-20000;
Cpa=20;
Cpb=20;
Kc1=1000;
R=0.001987;
dH1=-20; % dH x 10^-3
X=0:0.01:1.0;
%Derived Equations
Temp=325+((X*20000)/(40));
Kc=1000*(exp((-20/0.001987)*((1/305)-((1./Temp)))));
XE=((4.*Kc)-sqrt(((16*(Kc.^2))-(12*(Kc-4).*Kc))))./(2.*(Kc-4));    % changed / to ./
plot(Temp,XE);