Question

Click an item in the list or group of pictures at the bottom of the problem and, holding the button down, drag it into the correct position in the answer box. Release your mouse button when the item is place. If you change your mind, drag the item to the trashcan. Click the trashcan to clear all your answers.
Add the following polynomials, then place the answer in the proper location on the grid.

Answer 1

Add the following polynomials:
All polynomials are already ordered according to their degree (exponent), and therefore you can just add straight down in columns.
For x3: 2 + 1 - 3 = 0
For x2: -4 + 6 + 2 = 4 
For x: 6 - 8 -4 = -6
Constants: -3 + 12 - 7 = 2

The answer is:
4x^2 - 6x + 2