Analysis: If the sum of two sides is 12-5=7 according to the meaning of the question, then 7= 1+6=2+5=3+4, and then the sum of any two sides in the triangle is greater than the third side, and the difference between any two sides is less than the third side, it can be solved.

The answer is as follows

Because: the length of one side of a triangle is 5, the length of the other two sides is an integer, and the perimeter is 12.

So: the sum of the two sides is 12-5=7.

Because: 7= 1+6=2+5=3+4.

So: the three sides of this triangle are 5, 5, 2 or 3, 4, 5 respectively.

Extended data:

This question examines the trilateral relationship of a triangle. In a triangle, the sum of any two sides is greater than the third side, and the difference between any two sides is less than the third side.

The perimeter formula of triangle: C = A+B+C b+c.

Formula: A is the base of a triangle, and B and C are two waists.

Application example: If the base A of a triangle is 6cm and the waist lengths B and C are 5cm, then the perimeter C=5+5+6= 16cm.