There are two costs involved:
1) the cost for lunch, which is given as a rate per student: $7.25/student
2) the cost for the trip which is $443.75 to be divided by the 25 students, so it is $443.75 / 25 = $17.75/student
Now, you can add up those two costs per student to have the total cost per student:
$7.25 + $17.75 = $25.00/student
Answer: $25.00
Its going to be 4 .............
Answer:
a = (r/x) -b
x = -14
Step-by-step explanation:
r=x(a+b)
Divide each side by x
r/x = a+b
Subtract b
r/x -b = a
x/2=-7
Multiply each side by 2
x/2*2 = -7*2
x = -14
I am going to explain this using the substitution method, considering it appears to be the best in this situation.
We know (from the bottom equation) that y can equal 3x+20. Using this knowledge, we substitute the y in the top equation for 3x+20. Now, we have an equation that looks like this:
3x+20=x^2+2x
Now we need to move x to one side and then do some radicals (square roots).
Subtract the 2x on the right (since it is smaller, negatives = NONONO), which will give you
x+20=x^2
Now, we take the square root of both sides to get
rad(x+20)=x
Now we have to simplify. 20 doesn't have a square root, but 4 goes into 20, and 4 has a square root of 2. This now becomes
2rad(x+5)
This doesn't simplify any further... we have a problem... no way to isolate x as far as my knowledge goes... Sorry, can't help you any further than that, but another person or your teacher might be able to. R.I.P...