Question

solve the following simultaneous equations using cramer's rule. 5x+3y=-11 ; 2x + 4y=-10​

Answer 1

Answer:

x = -1 and y = -2

Step-by-step explanation:

These equations correspond to the matrix equation

$\left(\begin{array}{cc}5&3\\2&4\end{array}\right)\left(\begin{array}{c}x\\y\end{array}\right) = \left(\begin{array}{c}-11\\-10\end{array}\right)$

The determinant of the coefficient matrix is

$|A|=\left|\begin{array}{cc}5&3\\2&4\end{array}\right| = (5)(4)-(3)(2)=20-6=14$

By Cramer's rule

$x = \frac{\left|\begin{array}{cc}-11&3\\-10&4\end{array}\right|}{\left|\begin{array}{c}A\end{array}\right|} = (-44+30)/14 = -14/14 = -1$

and

$y = \frac{\left|\begin{array}{cc}5&-11\\2&-10\end{array}\right|}{\left|\begin{array}{c}A\end{array}\right|} = (-50+22)/14 = -28/14 = -2$

Answer 2

Step-by-step explanation:

solving of equations...