Square A has a side length #(2x -7)# and Square B has side length #(-4x+18)#. How much bigger is the perimeter of Square B than Square A?

1 Answer
Feb 21, 2017

# = -24 x +100# for #7/2 < x < 9/2#

Explanation:

Perimeter of Square A = #4(2 x - 7) =8 x - 28# unit.
note : since the unit of length cannot be -ve value, therefore #x>7/2# for Square A.

Perimeter of Square B = #4(-4 x + 18) =-16 x + 72# unit
note : since the unit of length cannot be -ve value, therefore #x<18/4 or 9/2# for Square B.

Consideration to both of notes, the values x shall be #7/2 < x <9/2#
The different perimeter between Square B and Square A = Perimeter of Square B - Perimeter of Square A.

#= (-16 x + 72) -(8 x -28)#

#= -16 x + 72 -8 x +28#

# = -24 x +100# for #7/2 < x < 9/2#