∣2−4x9∣=58\begin{vmatrix} 2 & -4 \\ x & 9 \end{vmatrix} = 582x−49=58
→(2×9)−(−4×x)=58\rightarrow (2 \times 9) - (-4 \times x) = 58→(2×9)−(−4×x)=58
18+4x=58→4x=58−18=4018 + 4x = 58 \rightarrow 4x = 58 - 18 = 4018+4x=58→4x=58−18=40
x=10x = 10x=10
