Simple....
in 5 boxes you have 125 dishes...how many per box?
125/5=25
So, how many dishes in 15 boxes?
25*15=375
This means that in 15 boxes there are 375 dishes.
Thus, your answer.
I think C I’m not sure but if you want me to explain I multiplied 12 x 10 and 20 x 6 and they both equal 120. So then I added 120 + 120 and got 240. Then u just added 8 because 8 was never use. Which will now look like 240 + 8 and that equal 248. :)
Ax + z = aw - y....subtract aw from both sides
ax - aw + z = -y....subtract z from both sides
ax - aw = -y - z....factor out a on the left side
a(x - w) = -y - z...divide both sides by (x-w)
a = (-y - z) / (x - w)