Answer:
circle = 5, triangle = 2, square = 6
Explanation:
If we look at the first and second equations, we see that circle + triangle + square = 13. Because triangle + square = 8, we can substitute this into the first equation, therefore, circle + 8 = 13 and circle = 5. Next, looking at the third equation, we see that circle + triangle = 7 and since circle = 5 we know that 5 + triangle = 7, therefore, triangle = 2. Finally, we can substitute triangle = 2 into the second equation which gives us 2 + square = 8, therefore, square = 6.