Answer:
the cost of one geranmium is $5
the cost of 9 daylily is $54
Explanation:
For this we have to make 2 equations one for each purchase made
let's identify the values of each one with letters
d = daylilies
g = geranimums
11d + 5g = $91
9d + 5g = $79
we are going to clear 5g since it is in the 2 equations
5g = 91 - 11d
and now we replace in the other equation the 5g by 91 - 11d
9d + 5g = $79
9d + (91 - 11d) = $79
we cleared d
9d + (91 - 11d) = $79
9d - 11d = 79 - 91
-2d = - 12
d = -12/-2
d = 6
1 daylily costs $6
9 daylily costs $6 * 9 = $54
to know the value of g we only replace d in the initial equation
11d + 5g = $91
11(6) + 5g = 91
66 + 5g = 91
5g = 91 - 66
5g = 25
g = 25/5
g = 5
the value of g is $5