The slope of the the solving equation is triple the slope of the given equation. Therefore, the y coefficient must also be triple of the other y coefficient.
These types of questions involve ratios. So 2.5: 25 is equal to 25 : 250 and all i did was multiply both sides by 10. Then it says that he only has 1 pound of ground beef so 25* 1/25 is equal to one, and then 250 * 1/25 is equal to 10.