Justin bought 40 packs of baseball cards for a discounted price of $64.if he sells 10 packs of baseball cards to a friend at cost, how much should he charge?

option (b) is correct

step-by-step explanation:

to find the solution of this system, we need to convert it into reduced row-echelon form. we have,

after applying row operations r2 -> r2/2 and r3 -> r3/3, we get,

where does the z at is it on the x axes or on the y axes any way if it is on the y axes put it horizontally and if it is on the x axes put it vertically