Question

Can the sides of a triangle have lengths 18, 19, and 7?

Answer 1

yes it can be

because the triangle inequality theorem described that for any triangle the sum of the length of two sides are always grater than the third side

then 18, 19, 7 can the three side of a triangle

Answer 2

Yes. The rule is that any 2 sides of a triangle should be larger than the third. Therefore, it is possible to have lengths of 18, 19, and 7.