How do i write a set operation for venn diagrams?

Write two subtraction equations that are equivalent to 5 + 12 = 17.

What is the location of point g, which partitions the directed line segment from d to f into a 5: 4 ratio? –1 0 2 3

At a pizza shop 70% of the customers order a pizza 25% of the customers order a salad and 15% of the customers order both a pizza and a salad if s customer is chosen at random what is the probability that he or she orders either a pizza or a salad