Answer:
7-(-2)=7+2
Step-by-step explanation:
7-(-2)=9
7+2=9
Hope this helps!
Answer: 504
Step-by-step explanation:
When we select r things from n things in a order , we use permutations.
Formula for permutation: 
Given : The number of family members who are potential kidney donors. = 9
Number of people needed to be selected for best match, a second-best match, and a third-best match ( in an order)=3
Then, the number of possible orders are = 

Hence, the number of possible orders 504.
Answer:
(x - 9)2 Step-by-step explanation:
Answer:
z=98 and 5x+57 and z are supplementary.
Step-by-step explanation:
vertical angles theorem