33 photos in a 4x to 7x ratio
4x + 7x = 33
11x = 33
x = 3
33 photos can be put in a 4(3) to 7(3) ratio
which is a 12 to 21 ratio
so 12 photos on one side, and 21 on the other side to get the ratio of 4 to 7
Note:
<span>a(b) = ab = a x b = a times b</span>

![\bf \stackrel{\textit{multiplying both sides by LCD of 3}}{3(y+5)=3\left[ \cfrac{5}{3}(x-3) \right]}\implies 3y+15=5(x-3) \\\\\\ 3y+15=5x-15\implies -5x+3y=-30\implies \stackrel{\textit{multiplying by -1}}{5x-3y=30}](https://tex.z-dn.net/?f=%5Cbf%20%5Cstackrel%7B%5Ctextit%7Bmultiplying%20both%20sides%20by%20LCD%20of%203%7D%7D%7B3%28y%2B5%29%3D3%5Cleft%5B%20%5Ccfrac%7B5%7D%7B3%7D%28x-3%29%20%5Cright%5D%7D%5Cimplies%203y%2B15%3D5%28x-3%29%0A%5C%5C%5C%5C%5C%5C%0A3y%2B15%3D5x-15%5Cimplies%20-5x%2B3y%3D-30%5Cimplies%20%5Cstackrel%7B%5Ctextit%7Bmultiplying%20by%20-1%7D%7D%7B5x-3y%3D30%7D)
bearing in mind the standard form uses all integers, and the x-variable cannot have a negative coefficient.
7=2x + 15 2x= -8 x= -4
<span>8= 3x 8= 3x+0 3x +-8 3(-4) +-8 -12 - 8 </span>
<span>Final Answer -20</span>