I don't understand this problem. I thought the answer was -9 but my teacher wouldn't accept it. please help. If using the method of completing the square to solve the quadratic equation x² + 3x + 9 = 0, which number would have to be added to "complete the square"?

The input to the function is x and the output is y. write the function such that x can be a vector (use element-by-element operations). a) use the function to calculate y(-1.5) and y(5). b) use the function to make a plot of the function y(x) for -2 ≤ x ≤ 6.

Asap! will mark brainliest! ( respond asap, it's urgent! : )) what is the slope for equation y =-3x + 8

Aresearch study is studying the effects of a new drug for osteoporosis alzheimer's disease (ad) for women above the age of 65 years. a group of individuals with osteoporosis is randomized into two groups. one group is treated conventionally, and the second group is treated with the new medication. assessments are made at 3, 6, 12, 36, and 48 months. the conventionally treated group is assessed for ad using a serum blood test, and the treatment group is assessed for ad using a pet radiotracer that binds to beta-amyloid plaques. in comparing these 2 trial arms, the authors of the study may encounter which type of bias? a. selection bias on the risk of developing b. measurement bias c. confounding bias d. recall bias e. lead-time bias