What is 9ab + 3b^2 - 7b^2 + 8ab - 12 simplified?

Bed a is seven feet long. bed b is 7/8 of bed a. bed c is 7/8 of bed b. bed d is 7/8 of c. a. come up with an expression for the length of bed d. b. what is the length of bed d?

Rockwell hardness of pins of a certain type is known to have a mean value of 50 and a standard deviation of 1.1. (round your answers to four decimal places.) (a) if the distribution is normal, what is the probability that the sample mean hardness for a random sample of 8 pins is at least 51?

Right triangle xyz has a right angle at vertex y and a hypotenuse that measures 24 cm. angle zxy measures 70º. what is the length of line segment xy? round to the nearest tenth. 8.2 cm 8.7 cm 22.6 m 25.5 cm