87+21y=24x
-9x+27+9y=0
solve by elimination

Which statement is always true? a negative exponent cannot be part of an expression's numerator. a negative base raised to the power of 2 has a negative value. a negative base raised to the power of 2 has a positive value. any number to the first power is zero.

Determine if the outside temperature is a function of the time of day or if the time of day is a function of temperature and explain why or why not.

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