For which of the following systems of inequalities is the intersection of the boundary lines included in the solution? [hint: you do not need to graph]

A. x+y<=4, x+5y>=6
B. x+y<=4, x+5y>6
C. x+y<4, x+5y>=6
D. x+y<4, x+5y>6

Researchers were interested in whether relaxation training decreases the number of headaches a person experiences. they randomly assigned 20 participants to a control group or a relaxation training group and noted the change in number of headaches each group reported from the week before training to the week after training. which statistical analysis should be performed to answer the researchers' question?

Jason went to an arcade to play video games. he paid $2 for every 11 tokens he bought. he spent a total of $16 on tokens. which equation can be used to determine,t, the number lf tokens jason bought

You have 37 coins that are nickels, dimes, and pennies. the total value of the coins is $1.55. there are twice as many pennies as dimes. find the number of each type of coin in the bank.