Answer: the cost of one daylilies is $4
the cost of one ivy is $9
Explanation:
Let x represent the cost of one daylilies.
Let y represent the cost of one ivy.
Nicole and Kim bought their supplies from the same store. Nicole spent $99 on 9 daylilies and 7 pots of ivy. This means that
9x + 7y = 99 - - - - - - - -1
Kim spent $144 on 9 daylilies and 12 pots of ivy. This means that
9x + 12y = 144 - - - - - - - - -2
We will eliminate x by subtracting equation 2 from equation 1, it becomes
- 5y = - 45
y = - 45/-5 = 9
Substituting y = 9 into equation 2, it becomes
9x + 12 × 9 = 144
9x + 108 = 144
9x = 144 - 108 = 36
x = 36/9 = 4