Let r = ⟨7, 1⟩, s = ⟨–6, 2⟩, and t = ⟨–9, –3⟩. What is 10r + s – t?

The u-drive rent-a-truck company plans to spend $13 million on 320 new vehicles. each commercial van will cost $25 comma 000, each small truck $50 comma 000, and each large truck  $80 comma 000. past experience shows that they need twice as many vans as small trucks. how many of each type of vehicle can they buy?