(x + 6)/10 = (x + x + 6)/15;
15(x + 6) = 10(2x + 6);
15x + 90 = 20x + 60;
20x - 15x = 90 - 60;
5x = 30;
x = 30/5;
x = 6.
(x + 6)/10 = (x + x + 6)/15;
15(x + 6) = 10(2x + 6);
15x + 90 = 20x + 60;
20x - 15x = 90 - 60;
5x = 30;
x = 30/5;
x = 6.