Step-by-step explanation:
Let "c" be the original number of classrooms.
The 1200/c was the original number of students per classroom.
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Equation:
1200/(c-4) = (1200/c)+10
Multiply thru by c(c-4)
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1200c = 1200(c-4)+10c(c-4)
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1200c = 1200c-4800 + 10c^2-40c
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10c^2-40c-4800 = 0
c^2-4c-480 = 0
Factor:
(c-24)(c+20) = 0
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Positive solution:
c = 24 (# of classrooms originaly planned)
If you mean to put it into y=mx+b, then simply input m and b into that formula.
So it would be y=1/2x-4
Answer:

Step-by-step explanation:
The recursive rule tells you the initial term of the sequence is a1 = -3, and the common difference is d=7. (7 is the value added to one term to get the next term.)
Putting these values into the formula for the explicit rule gives ...
an = a1 +d(n -1)
an = -3 + 7(n -1)
Answer:
Anna will need to deposit 
Step-by-step explanation:
we know that
The compound interest formula is equal to
where
A is the Final Investment Value
P is the Principal amount of money to be invested
r is the rate of interest in decimal
t is Number of Time Periods
n is the number of times interest is compounded per year
in this problem we have
substitute in the formula above and solve for P
Since these two have the same power and variable, you can just subtract right away. It’s going to be 7x^1/5