Can't figure it out plz help

Question

The width of a rectangle is 13 m less than its length. The area of the rectangle is 48 m2. Find the dimensions of the rectangle

Answer 1

Width = L - 13

 

Area = LW

 

Area = L(L - 13)

 

48 = L²  - 13L

 

L² - 13L - 48 = 0

 

Now factor

 

(L -16)(L + 3) = 0

 

L = 16      or L = -3 (negatives here are meaningless)

 

Therefore , L = 16 and and the width = L - 13, 16 - 13 = 3

 

W = 3

L = 16

Answer 2

draw a rectangle

label long sides X

label short sides X-13

two sides are X

two sides are X-13

add all 4 sides to equal 48

x + x + x + x -13 -13 = 48

4x-26=48

4x=74

x=18.5

so

two sides are 18.5m

two sides are 5.5

proof

5.5 + 5.5 +18.5 + 18.5 = 48