Solve application problems using quadratic equations

Question

The area of a rectangle is 46 square inches. If the length is 4 times the width, then find the dimensions of the rectangle. Round off your answer to the nearest hundredth?

Answer 1

LW = 46

L=4W

so by substituting 2nd into 1st you get

4W(W) = 46

4W^2 = 46

W^2 = 46/4=23/2 = 11.5. then take square roots of both sides

W=sqr11.5 = 3.391 rounded to nearest hundredth = 3.39 inches

L= 4(3.391)=13.564 rounded = 13.56 inches