Exercise · ZW-GAUSSIAN-ELIMINATION-002 · ★☆☆ Basic
Solve \(\begin{cases}x+y=3\\2x-y=0\end{cases}\).
Choose one option.
Show answer
- A. \((x,y)=(1,2)\)
Explanation
Adding the equations: \(3x=3\), so \(x=1\) and \(y=2\).
Review the concept: Gaussian elimination
Gaussian elimination solves a linear system by reducing its augmented matrix, with coefficients \(A\) and vector \(\mathbf b\), to an echelon form \(U\) using elementary row operations.
\[[A\mid \mathbf b]\ \longrightarrow\ [U\mid \mathbf c]\]
More practice problems: gaussian elimination
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