How to simplify 5k + 3 + 2j – 2 – k

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?

What are the solutions of the system? solve by graphing. y = x^2 + 3x + 2 y = 2x + 2

Hey hotel charges guests $19.75 a day to rent five video games at this rate which expression can be used to determine the charge for renting nine video games for one day at this hotel? pls