I think your question is missed of key information, allow me to add in and hope it will fit the original one. Please have a look at the attached photo.
My answer:
a. Carpeting a floor
To carpet a floor, you need to find the area of it so that we can have an appropriate plan to buy material. Hence, it represented by are
b. Fencing a garden
If you want to fence a garden, we need to know the the total length around it or we can say that is the perimeter of the garden. So this situation is represented by perimeter.
Your answer is area because area refers to a region, while perimeter only refers to the surrounding boundary of a figure. If you're going to carpet a floor, you will want to cover the entire area of the floor.
3x+4=-5x-3+15 First combine like terms: 3x+4=-5x+12 Get x on one side: 3x+4=-5x+12 -3x -3x 4=-8x+12 Next get x by itself: 4=8x+12 -12 -12 -8=8x Now divide one more time to get x by itself since 8x is 8 times x and we must do the opposite (÷). -8/8=8x/8 -1=x ---> x=1
