A store bought a pair of shoes for $40 and sold it for 100

Sadie computes the perimeter of a rectangle by adding the length, l, and width, w, and doubling this sum. eric computes the perimeter of a rectangle by doubling the length, l, doubling the width, w, and adding the doubled amounts. write an equation for sadie’s way of calculating the

What is the axis of symmetry of the function f(x)=-(x+ 9)(x-21)

Which inequality statement describes the two numbers on a number line? "? 7 and a number 5 units to the right of ? 7"