Explicación paso a paso:
[tex]5x + 4y = 23 \\ 5x = 23 - 4y \\ x = \frac{23 - 4y}{5} [/tex]
[tex]4x + 7y = 26 \\ 4x = 26 - 7y \\ x = \frac{26 - 7y}{4} [/tex]
[tex] \frac{23 - 4y}{5} = \frac{26 - 7y}{4} \\ 92 - 16y = 130 - 35y \\ 92 - 130 = - 35y + 16y \\ - 38 = - 19y \\ 19y = 38 \\ y = \frac{38}{19} = 2[/tex]
[tex]4x + 7y = 26 \\ 4x + 7 \times 2 = 26 \\ \\ 4x + 14 = 26 \\ 4x = 26 - 14 \\ 4x = 12 \\ x = \frac{12}{4} = 3[/tex]
[tex]5 \times 3 + 4 \times 2 = 23 \\ 4 \times 3 + 7 \times 2 = 26[/tex]
