ayuden porfavor . determine 4 ala potencia x + 4 ala potencia -x si se sabe que 2 ala apotencia x + 2 ala potencia-x = 3

Solve the system of equations. y= 2x y= x^2 - 15

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?

How can you construct perpendicular lines and prove theorems about perpendicular lines