Answer:
15
Explanation:
We know that both of the angles with are a value are going to be equal due to the laws of angles, specifically as these are vertically opposites they'll be the same as long as the two lines that intersect are straight.
So we now have 60 = x + 45,
Wwich can be rearanged too 60 - 45 = x
60 - 45 = 15, so x must be 15 degrees