Your cousin is taking the train to washington to visit her parents. she has at most $15 to spend on snacks and reading materials. granola bars cost $1.15 each and magazines cost $1.25. if your cousin buys the same number of granola bars and magazines. how many can she buy? this is an inequality problem.

If  she only has $15 to spend we will use the ≤ sign as this will make sure we either spend less or exactly $15. We will assign x to number of snacks and y to number of magazines, so our magazines will be 1.25y and snacks are 1.15x. since we hav two different variables, we need a second equation, if we will get equal of either, that means x=y so now we have

since x=y, we can replace either x or y in our second equation

solve:



since we cant have .25 of either one, we will say y is 6 and since x=y, that means x is 6 too

Subtracting is the opposite of adding