The length plus the width of a rectangle is 10. let x represent the length. the equation for the area y of the rectangle is y = x(10 – x). the y-value of the vertex gives the value of the of the rectangle.

Afactory makes propeller drive shafts for ships. a quality assurance engineer at the factory needs to estimate the true mean length of the shafts. she randomly selects four drive shafts made at the factory, measures their lengths, and finds their sample mean to be 1000 mm. the lengths are known to follow a normal distribution whose standard deviation is 2 mm. calculate a 95% confidence interval for the true mean length of the shafts. input your answers for the margin of error, lower bound, and upper bound.

In which direction does the left side of the graph of this function point? f(x) = 3x3 - x2 + 4x - 2

How can you find the mean absolute deviation (mad) for this set of data?