Answer:

Explanation:
First I identified that 2 of side lengths are the same, being 5. Then 88° is inbetween them, so I now know that both missing angles will be equal. This works with all triangles, if 2 sides equal the same then 2 angles will be equal.
So now we know a triangles angles always add up to be 180, so now we just subtract and divide.

So now we know the sum of both missing angles so we can just divide the value in half because both angles are the same.

Now we know x=46°