3a + 6b = 45
2a - 2b = -12....multiply by 3
----------------
3a + 6b = 45
6a - 6b = - 36 ...(result of multiplying by 3)
---------------add
9a = 9
a = 1
3a + 6b = 45
3(1) + 6b = 45
3 + 6b = 45
6b = 45 - 3
6b = 42
b = 7
solution is : (1,7)
The difference between each number in the dollars fund is 25
209 - 184 = 25
184 - 159 = 25
so....in the ? space......134 - 25 = 109 <==
This is the answer if your question
It's asking for the "perimeter" of the molding as far as I can tell,
namely, how long is the border of that molding
notice the picture here