Evaluate $4 \times 4$ Determinant $$\left| \begin{array} { c c c c } 1 & 3 & 6 & 8 \\- 7 & 4 & 0 & 9 \\- 4 & 6 & 3 & 8 \\3 & 1 & 5 & 4\end{array} \right|$$

Q188: Solve the system. <span class="ql-formula"

Q189: Solve the system by the substitution

Q190: The matrix is the reduced echelon

Q191: Use the appropriate property of determinants

Q192: A system of two linear equations can

Q194: In a system of three linear equations,

Q195: Solve the system. <span class="ql-formula"

Q196: Solve the system by the substitution

Q197: Use Cramer s rule to find

Q198: Use the appropriate property of determinants