Which expression is equivalent to 15x – 2(3x + 6)?

a. 3(3x + 4)
b. 3(3x – 4)
c. 9x + 12
d. 10x – 12

Which describes the difference between the graph of f(x)=x^2 and g(x)=-(x^2-2)

Can someone factor this fully? my friend and i have two different answers and i would like to know if either of them is right. you in advance. a^2 - b^2 + 25 + 10a

Suppose babies born after a gestation period of 32 to 35 weeks have a mean weight of 25002500 grams and a standard deviation of 800800 grams while babies born after a gestation period of 40 weeks have a mean weight of 27002700 grams and a standard deviation of 385385 grams. if a 3232-week gestation period baby weighs 21252125 grams and a 4040-week gestation period baby weighs 23252325 grams, find the corresponding z-scores. which baby weighs lessless relative to the gestation period?