Is (-2, 1) a solution to the system
x -y = -3
y = -2x + 5

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?

Evaluate cos2θ for cosθ = square root of 3/2

Spencer has 1/3 pound of nuts he divides them equally into 4 bags what fraction of a pound of nuts is in each bag