To solve this exercise we must first identify our variables
• C, = Total cost
,• r ,= number of roses
,• v ,= number of vases
Now, with these variables we will formulate the equations that model the price of each of the flower shops. We have to take into account that Brad is only going to buy one vase
[tex]v=1[/tex]Silvergroce Florist
[tex]\begin{gathered} C=3r+20v \\ C=3r+20(1) \\ C=3r+20\to(1) \end{gathered}[/tex]Noah's Flowers
[tex]\begin{gathered} C=1r+30v \\ C=r+30(1) \\ C=r+30\to(2) \end{gathered}[/tex]We have two equations (1) and (2), to find the total cost that is the same in both flower shops, we only have to equal them to find the number of roses that Brad should buy
[tex]\begin{gathered} 3r+20=r+30 \\ 3r-r=30-20 \\ 2r=10 \\ r=\frac{10}{2} \\ r=5 \end{gathered}[/tex]Brad must buy 5 roses so that it costs the same at both florists. To know the cost we substitute in any equation (1) or (2) the number of roses
[tex]\begin{gathered} C=r+30 \\ C=5+30 \\ C=35 \end{gathered}[/tex][tex]\begin{gathered} C=3r+20 \\ C=3(5)+20 \\ C=15+20 \\ C=35 \end{gathered}[/tex]
Answer:
y = 20 + 3x
y = 30+x
( 5,35)
Step-by-step explanation:
Writing and solving a system of equations
Silvergrove Florist: 20 + 3x
Noah's Flowers: 30 + 1x where x is the number of roses
We want to know when they are equal
20+3x = 30+1x
Subtract x from each side
20+3x-x = 30+x-x
20+2x = 30
Subtract 20 from each side
20+2x-20 = 30-20
2x = 10
Divide by 2
2x/2 = 10/2
x = 5
The number of roses is 5
The cost is
30 +x = 30+5 = 35
(5,35)
