Solve the given system, using the substitution method.
y = 3x – 7
6x – 2y = 12
a.
there is no solution.
b.
there are an infinite number of solutions.
c.
(12, 14)
d.
(14, 12)

Rockwell hardness of pins of a certain type is known to have a mean value of 50 and a standard deviation of 1.1. (round your answers to four decimal places.) (a) if the distribution is normal, what is the probability that the sample mean hardness for a random sample of 8 pins is at least 51?

Afrequency table of grades has five classes (a, b, c, d, f) with frequencies of 3, 13, 14, 5, and 3 respectively. using percentages, what are the relative frequencies of the five classes?

Credit card a offers an introductory apr of 3.4% for the first three months and standard apr of 15.7% thereafter,