Solve the equation: x^2 - 6x = 7

a. x = 7 , 1
b. x = -7 , 1
c. x = 7 , -1

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