0.8 * (5 - x) - 1.2 * (x + 4) = -2.8;
0.8 * 5 - 0.8x - 1.2x - 1.2 * 4 = -2.8;
4 - 0.8x - 1.2x - 4.8 = -2.8;
-0.8x - 1.2x = -2.8 + 4.8 - 4;
-2x = -2;
x = 1.
0.8 * (5 - x) - 1.2 * (x + 4) = -2.8;
0.8 * 5 - 0.8x - 1.2x - 1.2 * 4 = -2.8;
4 - 0.8x - 1.2x - 4.8 = -2.8;
-0.8x - 1.2x = -2.8 + 4.8 - 4;
-2x = -2;
x = 1.