What is the factored form of these expressions?
1. d2 + 18d + 81
a. (d + 9)(d – 9)
b. (d + 9)2
c. (d – 81)(d – 1)
d. (d – 9)2

2. d2 + 22d + 121
a. (d + 11)2
b. (d – 11)2
c. (d – 11)(d + 11)
d. (d – 121)(d – 1)

3. r2 – 49
a. (r – 7)(r + 7)
b. (r + 7)(r + 7)
c. (r – 7)(r – 7)
d.(r – 7)(r + 9)

Match the vocabulary to the proper definition. in probability, two events in which 1. conditional probability the outcome of one event is independent of the outcome of a second event. 2. dependent events in probability, two events in which the outcome of one event is dependent on the outcome of a second event. the probability of an event in which the outcome of the event is conditional on the outcome of one or more different events. 3. independent events