4x - y = 6
2x - y/2 = 4 /multiply both sides by 2 to get rid of the fraction
4x - y = 6
4x - y = 8
This system has no solution because it contradicts itself.
A. 400, 500
The question mentions you make a profit, which is to make more money than what you spent or put in. All other choices would make the statement say you ended up having less money, which is money lost, not profit.
Well I tried doing it but depends what your trying to do with the equation but I got
x= -a/3 - 5d/3
Im not sure what the question is asking but my guess would be c)18.