Answer:
width = 2 units
Step-by-step explanation:
If the length of a rectangle is (x) units, then that means that the width of a rectangle is x - 4 units.
the area of a rectangle is length * width
so just substitute the values that we have now.
x (length) * (x-4) width = 12 (area of rectangle)
so that gives us
x^2 - 4x =12
subtract 12 from both sides
x^2 - 4x - 12 =0
now factor this equation
x^2 + 2x - 6x -12 = 0
x(x+2) - 6(x+2) = 0
(x-6)(x+2) = 0
x = 6, or x = -2 REMEMBER THAT VALUE OF x = LENGTH, IT CANNOT BE NEGATIVE AS YOU CANT HAVE NEGATIVE VALUE OF A SIDE
length = 6, and width = 6 -4 = 2
Answer:
W=2 units
Step-by-step explanation:
Length=L
Width=L-4
Area of a rectangle= L*W
L(L-4)=12
L^2-4L=12
L^2-4l-12=0
Now we have a quadratic equation
(L-6)(L+2)=0
L=6, L=-2
L cannot be -2 because it is negative, so L must be 6.
BUT it is asking for the width
and it is given that the width is the length minus 4 units, so
6-4= 2 units
