If ý = (-7, 2) and Z = (1, -8), find the difference y - z. ý -z = 0

Marissa can buy 3 oranges for $1.35 4 oranges for $.80 or 5 oranges for $2.25 marissa can buy 10 oranges for a price that fits this pattern or a bag of oranges for $4.25 which way costs less for 10 oranges