Can you help me to do this?

clc
close all
clear all
syms T2 T3 T4 x4 x3 ;
x2 = [T2 ;T3 ;T4];
T1 = 303;
k = 10;
L = 3;
h = 10;
figure(1)
for x3 = [1 0.1 0.01 0.001]
    x1 = [-2 1 0;1 -2 1;0 -1 1+x3];
 equ = x2 == inv(x1)*[-100*(x3)^2-303; -100*(x3)^2; 100*(x3)^2+303*x3];
 disp(equ)
 plot(x3,equ,'b')
 hold on
end

[Rik]

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