Use Cramer's rule to find the solution of the system,if possible.? $$\left\{ \begin{aligned}
5 x - y & = 12 \
x + y & = 0
\end{aligned} \right.$$ ?
A)x = 2,y = -2
B)x = 5,y = -12
C)x = 5,y = -5
D)The system is inconsistent.
E)The equations are dependent.

Question

Quizplus · Accepted Answer

Cramer's rule involves calculating determinants. The determinant of the coefficient matrix is $5(1) - (-1)(1) = 6$. For $x$, replace the first column with the constants to get determinant $12(1) - 0(1) = 12$, so $x = 12/6 = 2$. For $y$, replace the second column, getting $5(0) - 12(1) = -12$, so $y = -12/6 = -2$.

Use Cramer's Rule to Find the Solution of the System,if {5x−y=12x+y=0\left\{ \begin{aligned}5 x - y & = 12 \\x + y & = 0\end{aligned} \right.{5x−yx+y​=12=0​

Use Cramer's Rule to Find the Solution of the System,if $\left\{ \begin{aligned}5 x - y & = 12 \\x + y & = 0\end{aligned} \right.$