M x+ B = y solve for B

A x+ B y = C solve for x

Bh/2 = A, solve for h

Jane moves from a house with 71 square feet of closet space to an apartment with 45.44 square feet of closet space. what is the percentage decrease of jane’s closet space?

Math i have no idea how to do a and b

If johnny ate 5 cans of sugar, but in the kitchen they only had 3. what did johnny eat? (he found a secret stash btw.)