Ответ:
3x - 4y = 48 \\ \frac{4}{5} x - 3y = 7 = > 4x - 15y = 35 \\ x = \frac{1}{3} (4y + 48) \\ \frac{4}{3} (4y + 48) - 15y = 35 \\ 16y + 192 - 45y = 105 \\ 29y = 87 \\ y = 3 \\ x = \frac{1}{3} (12 + 48) = 20" alt=" \frac{1}{4} x - \frac{1}{3} y = 4 = > 3x - 4y = 48 \\ \frac{4}{5} x - 3y = 7 = > 4x - 15y = 35 \\ x = \frac{1}{3} (4y + 48) \\ \frac{4}{3} (4y + 48) - 15y = 35 \\ 16y + 192 - 45y = 105 \\ 29y = 87 \\ y = 3 \\ x = \frac{1}{3} (12 + 48) = 20" align="absmiddle" class="latex-formula">