A) If you only sample people in a sports supply store, your sample will be biased. People in a sports supply store are more likely to be people that belong to a gym.
B) While it does not have necessarily the same amount of bias as sampling people in the sports supply store, people that go to a park are generally more likely to be people that exercise or have a gym membership.
C) Taking a random sample of people in town is a good way to get a non-biased sample. They are not necessarily predisposed to answer your question one way or another.
D) For the same reason as choice A, this is a biased sample.
C is the best choice.
Answer:
x 2 y -4
Step-by-step explanation:
13x = -54 -20y give it is A
-10x = 60 + 20y give it is B
A + B the sum of the left side of equation is equal to the sum of the right side of equation
13 + (-10x) = -54 -20y + 60 + 20y
3x = 60-54
3x = 6
x=2
so put the x value in A or B equation you can receive y value (B is easier)
y = -4