81x^2=25 solve by factoring

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?

Gregory draws a scale drawing of his room. the scale that he uses is 1 cm : 4 ft. on his drawing, the room is 3 centimeters long. which equation can be used to find the actual length of gregory's room?

Miranda is braiding her hair. then she will attach beads to the braid. she wants 1_3 of the beads to be red. if the greatest number of beads that will fit on the braid is 12,what other fractions could represent the part of the beads that are red?