Which of the following is the image of D after a rotation of 90° about the origin? (-1,-2)
(2,1)
(-2,1)

Geometry paper. i don't know how to do the rest. questions 5. 8. 9. and 10.

Hurry and answer this! circle x with a radius of 6 units and circle y with a radius of 2 units are shown which steps would prove the circles similar? translate the circles so they share a common center point, and dilate circle y by a scale factor of 4. translate the circles so the center of one circle rests on the edge of the other circle, and dilate circle y by a scale factor of 4. translate the circles so they share a common center point, and dilate circle y by a scale factor of 3. translate the circles so the center of one circle rests on the edge of the other circle, and dilate circle y by a scale factor of 3

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?