why am I getting the error "Incorrect number or types of inputs or outputs for function 'solve'."

my code is;

syms d;

s=solve('7*d + 3*e=71','d + 2*e=20');

s=[s.d s.e];

disp('1 dollar = ');

s(1)

disp('Eullar');

I am getting the error:

Incorrect number or types of inputs or outputs for function 'solve'.

Error in HW10 (line 2)

s=solve('7*d + 3*e=71','d + 2*e=20');

The qustion I am solving is:

"Seven dollars and 3 Euros make 71 Eullars.

One dollar and 2 Euros make 20 Eullars.

find out the value of a dollar in terms of Eullars"

Answer 1

[Star Strider]

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 = ');

1 dollar = 

vpa(s(1),3)

ans = 

7.45

disp('Eullar');

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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