It would be the first one, because the amount of corn he has, plus the amount of cotton he has equals 500 acres. Then, 250 is multiplied by x, because you don't know how much he is going to invest in the acre of corn, and same goes for the cotton, 615 is being multiplied by y, because you don't know how much cotton he desires. In conclusion, he can't spend more than 187,500, is what the first answer is saying. Hope it helps!