Algebra Word Problem?

The length of a rectangle is 1mm more than twice the width. If the area is 300 square mm, find the dimension of the rectangle?

Comments

  • L=Length, W=Width

    Length is 1 more than twice the width: L=1+2W

    Area is 300: L*W=300

    System of Eq's, plug and solve

    L*W=300

    (1+2W)*W=300

    2W^2+W=300

    2W^2+W-300=0

    Quadratic Formula

    W1= -12.5 W2= 12

    reject W1 because you cannot have negative width

    W=12

    L=1+2W=1+2*12=25

    Check:

    L*W=300

    25*12=300

    300=300 checks out

  • w(2w+1)=300 , 2w^2+w-300=0 , w=12 or -25/8 , length=25 and width=12

  • L = 1 + 2W

    WL = A

    W(1 + 2W) = 300

    W + 2W^2 = 300

    2W^2 + W - 300 = 0

    (-1 ± √2401) / 4

    W = {-12.5, 12} ignore negative answer

    W = 12 mm

    L = 25 mm

Sign In or Register to comment.