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

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Joshua on 23 Mar 2023
Commented: Star Strider on 12 Oct 2023
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"

Star Strider on 23 Mar 2023
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.
.
Harshit on 12 Oct 2023
i have the same problem my code is like this:
syms a b
>> exp_1='a*x+b*y-3';
>> exp_2='-x+2*a*y-5';
>> [x,y]=solve(exp_1,exp_2)
after this step it shows the same error
Star Strider on 12 Oct 2023
syms a b x y
exp_1=a*x+b*y-3;
exp_2=-x+2*a*y-5;
[x,y]=solve(exp_1,exp_2)

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