Given the function f(x)=x^2 and k=2, which of the following represents a horizontal shift?
f(x)+k, kf(x), f(x+k), f(kx)

Suppose that the price p, in dollars, and the number of sales, x, of a certain item follow the equation 4 p plus 4 x plus 2 pxequals56. suppose also that p and x are both functions of time, measured in days. find the rate at which x is changing when xequals2, pequals6, and startfraction dp over dt endfraction equals1.5.