16 is the sum of a number and 2.
What is the equation?

Which term best describes the association between variables a and b? no association a negative linear association a positive linear association a nonlinear association a scatterplot with an x axis labeled, variable a from zero to ten in increments of two and the y axis labeled, variable b from zero to one hundred forty in increments of twenty with fifteen points in a positive trend.

The parabola x = y² - 9 opens: a.)up b.)down c.) right d.)left

Find the center and the radius of the circle with the equation: x^2-2x+y^2+4y+1=0?