Solve the system.x - 7y = 5-3x + 21y = - 15
A. 
B. 
C. ?
D. 
Answer: B
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Provide an appropriate response. If you have 484 square feet in a rectangle and the length of one side is 24 feet, what is the length of the other side of the rectangle? Explain your reasoning.
What will be an ideal response?
Solve the problem.If s is proportional to t2, and s = 405 when t = 9, find s when t is 8.
A. 45 B. 72 C. 360 D. 320
In order to determine the effectiveness of a new vaccine that is alleged to cure "math anxiety," a study was conducted. One thousand volunteer college students enrolled in math courses across the U.S. were chosen. The 1000 students were broken up into two groups. Those enrolled in calculus courses were given the real vaccine. The students in developmental (remedial) math courses were given a fake vaccine consisting of sugared water. None of the students knew whether they were being given the real or the fake vaccine, but the researcher conducting the study knew. At the end of the semester the students were given a test that measured their level of math anxiety. The students in the treatment group showed significantly lower levels of math anxiety than those in the control group. On the
basis of this experiment the vaccine was advertised as being highly effective in fighting math anxiety.The results of this study should be considered unreliable because A. the sample was too small. B. the treatment and control groups represented two very different segments of the population. C. only college students were used. D. the treatment and control groups were not the same size. E. none of these
Scores in golf can be 0 (also called par), a positive integer (also called above par) or a negative integer (also called below par). Below are the scores of some members of a college golf team in a recent tournament. 
Find the average of the scores of the members shown. Represent the answer as an integer.
A. 0 B. -1 C. 1 D. 2