Answer:
8
Explanation:
Let's start with a simple fact: two sides of an isosceles triangle must be equal. Let's suppose the missing side is 4
That would mean that 4 + 4 equals 8. You must pick a side that exceeds 8, but you loose the property of 2 sides need to be equal.
So the answer has to be 8. The final size of the sides is 4 8 and 8. 4 and 8 exceed the third side (8).
8 and 8 certainly exceed 4.