The error about not enough input arguments will come from how you called the function -- which you didn't show us. Whatever that was, it won't have passed two arrays in as the function expects/requires.
BUT, your function is fatally flawed in several ways -- first the initial line undoubtedly needs the "dot" element-wise operators .* and .^ in place of the matrix operators * and ^.
It would appear that's all your function would need; the rest would simply sum those areas.
As you've written it, however, you overwrite the input variables s and h and so the remainder of the code is totally bogus.
SA=sqrt(3)/2*sum(s.^2 + 3.*s.*h);
If the function is designed for equilateral triangles as the comment says, then you don't need to pass the array of dimensions for each side -- and there would be only four surfaces, not five, anyways.
Then instead of the sum() you would just multiply the area of one side by 4.