-4(n - 6) = 12
n - 6 = -12/4 divide both sides by -4
n - 6 = -3
n = -3 + 6 add both sides by 6
n = 3
hope that helps, God bless!
8000 because 3 is less than 5 so you stay the same (which is 8)
Average rate is given by,

for section A, a=1, b=3
hope this helps.
Given :
On a map with a scale 1: 25000 .
The area of a lake is 33.6 square centimeters.
To Find :
The actual area of the lake.
Solution :
Let, actual area of lake is A.
So,

We know , 
Area in km² is :

Hence, this is the required solution.
Cramer's rule tells you that the value of x in the system of equations

is given by

In matrix terms, this is the determinant of the coefficient matrix with the right-side constants replacing the x-coefficients divided by the determinant of the matrix of coefficients. The value of y can be found by doing similar math with the numerator being the determinant of the coefficient matrix with the right-side constants replacing the y-coefficients. For systems of higher dimension, the column of right-side coefficients replaces each column of variable coefficients in turn.
For your equations, this evaluates to
