Write an equation that models the sequence 400, 200, 100, 50,
a) y = 400(2x)
b) y = 50 (2x)
c) y = 1/2x + 400
d)y = 400(1/2)x-1

One side of a rectangle is 7 centimeters shorter than six times the other side. find the length of the longer side if we also know that the perimeter of the rectangle is 266 centimeters.