The constant of variation is the number that relates two variables that are directly proportional or inversely proportional to one another.
Because the amount of money varies directly with the amount of gas the constant of variation is the price per gallon
$21.87÷9 = $2.43
2.43 is the answer.
A. 27 is a term so therefore the answer is A
You can rewrite radical form expressions by putting the expression to the power of 1/n, n depending on the radical. For example: sqrt2 = 2^(1/2) or cuberoot4= 4^(1/3). Vice versa with rational exponent equations: 5^(1/2) = sqrt5 or 3^4/3 = cuberoot3^4
for the system of equations
the three matrices needed to use Cramer's Rule are:
![D=\left[\begin{array}{cc}a_1&b_1\\a_2&b_2\end{array}\right] \\\\D_x=\left[\begin{array}{cc}c_1&b_1\\c_2&b_2\end{array}\right] \\\\D_y=\left[\begin{array}{cc}a_1&c_1\\a_2&c_2\end{array}\right]](https://tex.z-dn.net/?f=D%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7Da_1%26b_1%5C%5Ca_2%26b_2%5Cend%7Barray%7D%5Cright%5D%20%5C%5C%5C%5CD_x%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7Dc_1%26b_1%5C%5Cc_2%26b_2%5Cend%7Barray%7D%5Cright%5D%20%5C%5C%5C%5CD_y%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7Da_1%26c_1%5C%5Ca_2%26c_2%5Cend%7Barray%7D%5Cright%5D)
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To use Cramer's Rule we have to calculate the three determinants listed below of the matrices listed below.
![D=\left[\begin{array}{cc}2&5\\-3&-2\end{array}\right] \\\\D_x=\left[\begin{array}{cc}-13&5\\3&-2\end{array}\right] \\\\D_y=\left[\begin{array}{cc}2&-13\\-3&3\end{array}\right]](https://tex.z-dn.net/?f=D%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D2%265%5C%5C-3%26-2%5Cend%7Barray%7D%5Cright%5D%20%5C%5C%5C%5CD_x%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D-13%265%5C%5C3%26-2%5Cend%7Barray%7D%5Cright%5D%20%5C%5C%5C%5CD_y%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D2%26-13%5C%5C-3%263%5Cend%7Barray%7D%5Cright%5D)
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The value of the determinants are shown below.
The value of y is 
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270,275. The answer would be the last choice.
