For equality inside a symbolic expression, use double equal signs (==) —
syms d e
s=solve(7*d + 3*e == 71,d + 2*e == 20);
s=[s.d s.e];
disp('1 dollar = ');
vpa(s(1),3)
disp('Eullar');
The ability to use character arrays has been removed (depricated). Although ‘e’ was not included in the syms call, I assume it is a variable and not the exponential function e that is the exp function. If it should be ‘exp(1)’ (or the exponential function of some other argument), make the appropriate changes in your code.
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