Answer:
Roses = x = 100
Carnations = y = 110
Lilies = z = 120
Step-by-step explanation:
Roses = $4.50
Carnations = $3.00
lilies = $2.50
Total flowers ordered = 330
Total cost = $1,080
Let
Roses = x
Carnations = y
Lilies = z
x + y + z = 330
4.50x + 3y + 2.50z = 1080
There are 20
more lilies than roses
z = x + 20
Substitute z = x + 20 into the equations
x + y + (x + 20) = 330
4.50x + 3y + 2.50(x + 20) = 1080
x + y + x + 20 = 330
4.50x + 3y + 2.50x + 50 = 1080
2x + y = 330 - 20
7x + 3y = 1080 - 50
2x + y = 310 (1)
7x + 3y = 1030 (2)
Multiply (1) by 3
6x + 3y = 930 (3)
7x + 3y = 1030 (2)
Subtract (3) from (2)
7x - 6x = 1030 - 930
x = 100
Substitute x = 100 into (1)
2x + y = 310
2(100)+ y = 310
200 + y = 310
y = 310 - 200
= 110
y = 110
Substitute the value of x and y into
x + y + z = 330
100 + 110 + z = 330
210 + z = 330
z = 330 - 210
= 120
z = 120
Roses = x = 100
Carnations = y = 110
Lilies = z = 120