7+[latex] \frac{x}{10} [/latex]=[latex] \frac{x+9}{5} [/latex]

[latex]7+ \frac{x}{10} = \frac{x+9}{5} [/latex] [latex] \frac{70+x}{10} = \frac{x+9}{5} [/latex] 5(70+x)=10(x+9) 350+5x=10x+90 -5x=-260 x=52 Ответ: 52

[latex]7 + \frac{x}{10} = \frac{x+9}{5} [/latex] [latex] \frac{x}{10} + \frac{70}{10} = \frac{x+9}{5} [/latex] [latex] \frac{x+10}{70} = \frac{x+9}{5} [/latex] [latex] \frac{10(x+70)}{10} = \frac{10(x+9)}{5} [/latex] [latex]x + 70 = 2(x+9) 70 + x - (2x+9) = 2(x+9) - 2(x+9) 70 + x - 2(x+9) = 0 x - 2x - 18 + 70 = 0 (70 - 18) + (x - 2x) = 0 -x + (70 - 18) = 0 52 - x = 0[/latex] [latex]x = 52[/latex]