so basically in any paralellogram you have 2 pairs sides that are equal length and that are paralell to each other
hmm
we look at them that we have and look for matches
the only match we got is (-10,7) and (-10,-2)
means that one side is from (-10,7) o (-10,-2) and is 9 units long goint up
that (7,-4) must be the other poinr of the other side
since -4<-2, the missing point must be 9 units up from (7,-4)
9-4=3
(7,5) is the missing point
