How do you determine whether (-1, -1) and (1, -1) is a solution to #y < 2x + 1#?

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Answer 1 · 2015-07-23T00:07:06

#(1,-1)# is a solution to the inequality #y<2x+1#.

#y<2x+1#

Substitute #(-1,-1)# and #(1,-1)# for #x# and #y# into the inequality.

Point #(-1,-1)#
#x=-1#
#y=-1#

#-1<2(-1)+1# =

#-1<-2-1# =

#-1<-3#

This is a false statement. #(-1,-1)# is not a solution.

Point #(1,-1)#
#x=1#
#y=-1#

#-1<2(1)+1# =

#-1<2+1# =

#-1<3#

This is a true statement. #(1,-1)# is a solution.