The answer is 6 People. You make the two equations first 12.99x and 8.99x+20. And then make them equal each other 12.99x = 8.99x+20. Then you use algebra to solve for the x and you get an answer of 5. That is the number of people that would cause the two prices to break even (be the same price). So in order for the group rate to be the better deal you need 6 people to attend.
If the proportion of iris to roses in Nikki's garden is 2: 5, it means that for 25 roses: (2/5) = (10/25). Therefore to maintain the proportion by adding 20 roses: (2/5) = (18/45). The number of irises after the addition of roses will be 10 + 18 = 28 irises.
Answer: X=30
Hope that helped!!!
6 books at $ 8 = (6 * 8) = 48
if he got a discount of 20%, then he paid 80%
0.80(48) = 38.40 <== what he paid
The answer would have to be 4x^2y