Point A' is the image of point A under a rotation about the origin (0,0)
Determine the angles of rotation

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?

Solve for x and y: 217x + 131y = 913; 131x + 217y = 827

Annabelle's homework is 75% it took her three hours how long should she estimate it will take her to complete her homework.