Question

Matlab: Solve the following set of simultaneous equations. Remember, the system cannot be solved if the determinant of the coefficient matrix is zero. Use if statements to only display the results if the determinant is not zero

a) 3x1 + 2x2 + 4x3 = 5

2x1 + 5x2 + 3x3 = 17

7x1 + 2x2 + 2x3 = 11

b) x – y – z = 0

30x + 40y = 12

30x + 50z = 12

c) 4x + 2y + 2z + 4w = 0

3x + y + 4z + 7w = 1

2x + y + z + 2w = 1

3x + y + z + 3w = 4

Answer 1

%%% Matlab code

clc;
close all;
clear all;
%%%(a)
disp('a')
A=[3 2 4;2 5 3;7 2 2];
b=[5 17 11];
if det(A)==0
disp('Determinant is zero hence solution is not possible')
else
x=A/b;
fprintf('Solution is \n');
  
x
end

%%%(b)
disp('b')
A=[1 -1 -1;30 40 0;30 0 50];
b=[0 12 12];

if det(A)==0
disp('Determinant is zero hence solution is not possible')
else
x=A/b;
fprintf('Solution is \n');
  
x
end

%%%(c)
disp('c')

A=[4 2 2 4;3 1 4 7;2 1 1 2;3 1 1 3];
b=[0 1 1 4];
if det(A)==0
disp('Determinant is zero hence solution is not possible')
else
x=A/b;
fprintf('Solution is \n');
  
x
end

OUTPUT:

a
Solution is

x =

0.2138
0.2943
0.2092

b
Solution is

x =

-0.0833
1.6667
2.0833

c
Determinant is zero hence solution is not possible
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