please solve this and show your working out. thanks!
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Answer:
first
area of rectangle = l*b
= (3x-y+4) ( X+7)
= 3x²-xy + 4x+21x-7y+28
= 3x²-xy +25x-7y +28
Area of square = l²
= (x-2)²= x²- 4x +4
area of shaded region=( 3x²-xy +25x-7y +28) -(x²- 4x +4)
=2x²-xy +29x-7y+24
Step-by-step explanation: