Aftrekken geeft \(x = 5 \text{.}\)

\(\begin{rcases}2 x - 4 y = 4 \\ x = 5\end{rcases} \begin{matrix}2 ⋅ 5 - 4 y = 4 \\ -4 y = -6 \\ y = 1\frac{1}{2}\end{matrix}\)

De oplossing is \((x , y) = (5 , 1\frac{1}{2}) \text{.}\)

\(\begin{cases}6 a - 2 b = -2 \\ a + b = -1\end{cases}\) \(\begin{vmatrix}1 \\ 2\end{vmatrix}\) geeft \(\begin{cases}6 a - 2 b = -2 \\ 2 a + 2 b = -2\end{cases}\)

Optellen geeft \(8 a = -4 \text{,}\) dus \(a = -\frac{1}{2} \text{.}\)

\(\begin{rcases}6 a - 2 b = -2 \\ a = -\frac{1}{2}\end{rcases} \begin{matrix}6 ⋅ -\frac{1}{2} - 2 b = -2 \\ -2 b = 1 \\ b = -\frac{1}{2}\end{matrix}\)

De oplossing is \((a , b) = (-\frac{1}{2} , -\frac{1}{2}) \text{.}\)

\(\begin{cases}5 x + 3 y = -6 \\ 2 x + 2 y = 2\end{cases}\) \(\begin{vmatrix}2 \\ 3\end{vmatrix}\) geeft \(\begin{cases}10 x + 6 y = -12 \\ 6 x + 6 y = 6\end{cases}\)

Aftrekken geeft \(4 x = -18 \text{,}\) dus \(x = -4\frac{1}{2} \text{.}\)

\(\begin{rcases}5 x + 3 y = -6 \\ x = -4\frac{1}{2}\end{rcases} \begin{matrix}5 ⋅ -4\frac{1}{2} + 3 y = -6 \\ 3 y = 16\frac{1}{2} \\ y = 5\frac{1}{2}\end{matrix}\)

De oplossing is \((x , y) = (-4\frac{1}{2} , 5\frac{1}{2}) \text{.}\)