9) Adding up the numbers in the graph result in a total of 250 students. Adding 58 and 41 gives 99, so 99*100/250%= 39.6%
10) x^2-14x+49 can be factored as (x-7)^2
11) (1,3) is the answer because all of the other order pairs already have a domain value of it. For example, (7,0) is not possible to be part of the function because (7,2) already exists.
12) x^2-6x+9=12+9
(x-3)^2=21
To find the constant in question 12, first divide the middle term by 2, then square it. (assuming a=1 in the form of ax^2+bx+c)