(Solved): Azia wrote the numbers from 1 to 8 on the board, as shown below. Then she covered the numbers with ...

Azia wrote the numbers from 1 to 8 on the board, as shown below. Then she covered the numbers with triangles, squares, and a circle, as shown below. If you add the four numbers covered by the triangles, the sum is 10. If you add the three numbers covered by the squares, the sum is 20. Which number is covered by the circle? Show your work.