The other possible triangle is with ∠BCA as an obtuse angle.
Since for any angle ‘a’ between 0 and 180 degrees, sin a = sin (180-a), the triangle with ∠BCA = 180-60 = 120 deg and ∠CAB = 25 deg, is the other solution.
x = 4.1 sin 25 / sin 35 = 3.0
This is definitely meant as a test to see if the answer recognises that the sine rule produces two potential answers. It can be that either is valid or that other information makes only one valid, but both must be considered.