It if opens up, then the range will extednd to positive infinity.
if it opens down then the range will exted to negative infintiy.
there, 2 complete sentances
so we got range is from 4 to infinty so it opens up
Answer: 
Step-by-step explanation:
For this exercise it is important to remember the following:
The constant of proportionality, which is represented as "k", describe the constant ratio of two quantities that are proportional (the independent and dependent variables).
In this case we know that the independent quantity represents the total members of the band and the dependent quantity represents the woodwind members of the band.
Since the band consists of 3 woodwinds for every 7 members of the band, we can conclude that the constant of proportionality for this relationship is:

First, you have to distribute the -1 throughout the parentheses, which gives you 7x-3x-10=-46.
Then, you combine 7x and -3x, which gives you 4x-10=-46.
Then, you add 10 to both sides of the equation, which gives you 4x=-36.
FInally, you divide both sides of the equation by 4, which gives you x=-9.
Answer:
Step-by-step explanation:
f(x)=42-0.45(x) Solution 13.5 dollars expend in 30 Finishing nails
f(x)=42-0.60(x) Solution 18 dollars expend in 30 Common nails