Answer:
3) A
4) D
Explanation:
3)
Find any four points where y intersects with x on graph A
(-4 , 2) (-2 , 1) (4, - 2) (2 , -1)
Find the relationship(s) between x and y
(-4 , 2) (-2 , 1) (4, - 2) (2 , -1)
x = -2y x = -2y x = -2y x = -2y
It is shown that there is a direct proportional relationship between x and y, (x = -2y)
Repeat for graphs B, C, and D
Find any four points where y intersects with x on graph B
(3 , 2) (5 , 4) (-3 , -4) (-4 , -5)
Find the relationship(s) between x and y
x = 1.5y x = 1.25y x = 0.75y x = 0.8y
As you can see, there is not a constant direct proportional relationship between x and y. B is not the correct answer
Graph C
Find any four points where y intersects with x on graph C
(-5 , -3) (-1 , -3) (1 , -3) (5 , -3)
Find the relationship(s) between x and y
x = 1.67y x = 0.3y x = -0.3y x = -1.67y
Once again, there is not a constant direct proportional relationship between x and y, so C is not the correct answer
Graph D
Find any four points where y intersects with x on graph D
(2 , 1) (2 , 2) (2 , 3) (2 , 4)
Find the relationship(s) between x and y
x = 2y x = y x = 0.67y x = .5y
There is no direct constant relationship between x and y in this graph either.
Graph A is the only graph with a direct proportional relationship between x and y.
4) Allison wants to know whom seventh-grade students will vote for in the upcoming class president election.
A) Every member of the student council
Asking every member of the student council who they are voting for will not help Allison, because it is likely that there are multiple grades involved in the student council, when Allison just wants to know the opinions of seventh-graders. The student council also might have a different opinion than the general seventh-graders.
B) All 12 girls in Allison's homeroom class
It is likely that the girls at Allison's school have a very different opinion than the boys at her school, making this a bad data set.
C) Every tenth student who arrives at school on Monday
Allison only want to know the opinions of seventh-graders, not every tenth student at her school, which would consist of more than seventh-graders.
D) Every tenth name on a roster of all of the seventh-graders at the school
This data set would be the most useful to Allison because it is multi-gender, only seventh-grade, and consists of the general seventh-graders (not part of a special group).
D
Hope this helps :)