# help --- symbolic expression or function

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justlikethat on 11 Jun 2021
Commented: justlikethat on 11 Jun 2021
I've created a code for the symbol variables.
But I'm very embarrassed because the same error keeps coming out.
I'd appreciate it if you could tell me the solution.
syms x y z
one = sym('3*x +2*y - z = 10');
two = sym('-x + 3*y + 2*z = 5');
three = sym('x -y - z = -1');
[x,y,z] = solve(one,two,three)
error messeage ---->
The text vector and string type of the first argument can only specify variables or numbers. Use 'str2sym' to evaluate the string type and the text vector representing the symbol expression.
Error occurred: sym>tomupad (Line 1296)
S = convertChar(x);
Error occurred: sym (Line 234)
Error occurred: symsolve (Line 2)
one = sym('3*x +2*y - z == 10');
My grammar may be wrong because I am not good at English. Thank you!

Walter Roberson on 11 Jun 2021
The code you are using has not been valid since about R2017b.
syms x y z
one = str2sym('3*x +2*y - z = 10');
two = str2sym('-x + 3*y + 2*z = 5');
three = str2sym('x -y - z = -1');
[x,y,z] = solve(one,two,three)
x = y =
5
z = but better would be
syms x y z
one = 3*x +2*y - z == 10;
two = -x + 3*y + 2*z == 5;
three = x -y - z == -1;
[x,y,z] = solve(one,two,three)
x = y =
5
z = ##### 1 CommentShowHide None
justlikethat on 11 Jun 2021
Thank you so much!
Looks like the data I saw was out of date.

### More Answers (1)

KSSV on 11 Jun 2021
syms x y z
one = 3*x +2*y - z == 10;
two = -x + 3*y + 2*z == 5;
three = x -y - z == -1 ;
s = solve({one,two,three},x,y,z) ;
[s.x s.y s.z]
##### 1 CommentShowHide None
justlikethat on 11 Jun 2021
Thank you so much!
Looks like the data I saw was out of date.

R2021a

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