Ihad finish to solve the problems from the sentences, but i got stuck when i barely realized that the cost of one daylily i got is -2. i used this method by elimination.

You lost minus when you were adding two equations.
-176= - 22x -12y
144 =      6x   +12y
-32= - 16x
x=2

88=11x+6y,
88=11*2+6y
6y=66
y=11

Check:
88=11x+6y=11*2+6*11=88 True
144=6x+12y=6*2+12*11=12+132=144 True

The cost of daylilies is $2.
The cost of pot of ivy is $11.

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