Hi there!
In order to find the perimeter of the blanket, you'll need to multiply both values by 2, then add them together. Remember, the perimeter is the total exterior measurements. Use this equation: 2(3x + 7) + 2(2x - 3). Now, distribute: 6x + 14 + 4x - 6. Lastly, simplify: 10x + 8 cm.
Hope this helps!!
If there's anything else that I can help you with, please let me know!