Walk me through the process of solving for the area of this triangle (round to nearest tenth)

Which interval for the graphed function contains the local maximum? [–3, –2] [–2, 0] [0, 2] [2, 4]

Which value of c would make he following expression completely factored? 8x+cy

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?