Aftrekken geeft \(-b = -4 \text{,}\) dus \(b = 4 \text{.}\)

\(\begin{rcases}4 a + b = -6 \\ b = 4\end{rcases} \begin{matrix}4 a + 4 = -6 \\ 4 a = -10 \\ a = -2\frac{1}{2}\end{matrix}\)

De oplossing is \((a , b) = (-2\frac{1}{2} , 4) \text{.}\)

\(\begin{cases}4 x - 2 y = 4 \\ 3 x - y = 4\end{cases}\) \(\begin{vmatrix}1 \\ 2\end{vmatrix}\) geeft \(\begin{cases}4 x - 2 y = 4 \\ 6 x - 2 y = 8\end{cases}\)

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

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

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

\(\begin{cases}2 a - 2 b = 4 \\ 5 a + 3 b = 6\end{cases}\) \(\begin{vmatrix}3 \\ 2\end{vmatrix}\) geeft \(\begin{cases}6 a - 6 b = 12 \\ 10 a + 6 b = 12\end{cases}\)

Optellen geeft \(16 a = 24 \text{,}\) dus \(a = 1\frac{1}{2} \text{.}\)

\(\begin{rcases}2 a - 2 b = 4 \\ a = 1\frac{1}{2}\end{rcases} \begin{matrix}2 ⋅ 1\frac{1}{2} - 2 b = 4 \\ -2 b = 1 \\ b = -\frac{1}{2}\end{matrix}\)

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