как решить уравнение 100 (19 + (15 х-84) : 6=4

100 * (19 + (15 * х - 84) / 6) = 4;

19 + (15 * x - 84) / 6 = 4/100;

19 + (15 * x - 84) / 6 = 1/25;

25 * (19 + (15 * x - 84) / 6) = 0;

25 * 19 + 25/6 * (15 * x - 84) = 0;

475 + 25 * 15/6 * x - 25/6 * 84 = 0;

475 + 375/6 * x - 350 = 0;

125 + 375/6 * x = 0;

375/6 * x = - 125;

375 * x = 6 * (-125);

375 * x = - 750;

x = - 750/375;

x = - 2.