Ineed i don't really understand this

The perimeters of both are equal.
The side of the square is 12.
Therefore, its area equals to : 12² = 144

The rectangle base is 19.
Because it has the same perimeter as the square's, so rectangle perimeter is : 19 + 19 + side + side = 12 + 12 + 12 + 12
= 38 + 2side = 48
= 2side = 48 - 38
= side of rectangle = 5
Therefore, its area is 19 x 5 = 95

If you subtract it from the area of the square, you will get : 144 - 95 = 49.
So the answer is : the area of the square is 49 units largee than the area of the square (C)

Fuch th ckbj gcg ft tc jvuvuvu