Algebra 1 unit 8

Question

18) You are buying flowers for your garden. You need to buy 16 flowers in total. One daisy plant costs 8 1.60, and one rose plant costs $5.00. You spend a total of $63.00. Write a system of equations to represent the situation:

Answer 1

d = number daisies

r = number roses

 

d + r = 16          {equation 1}

1.6d + 5r = 63   {equation 2}

 

In equation 1 solve for one variable in terms 

of the other:

r = 16-d

Substitute into equation 2 and solve for d:

1.6d + 5(16-d) = 63

1.6d + 80 - 5d = 63

-3.4d = -17

d = -17/(-3.4)

d = 5 daisies

 

r=16-d = 11 roses

 

Check: 1.6(5)+5(11) = 8+55 = $63