A) 40a + 12a + a б) 31x - x - 15x - 10 в) 12m * 5 * 4 г) 3y * 15x * 20 упростить

a) 40 * a + 12 * a + a = a * (40 * 1 + 12 * 1 + 1) = a * (40 + 12 + 1) = a * (52 + 1) = a * 53 = 53 * a;

б) 31 * x - x - 15 * x - 10 = x * (31 * 1 - 1 - 15 * 1) - 10 = x * (31 - 1 - 15) - 10 = x * 15 - 10 = 15 * x - 10;

в) 12 * m * 5 * 4 = (12 * 5 * 4) * m = 60 * 4 * m = 240 * m;

г) 3 * y * 15 * x * 20 = 3 * 15 * 20 * x * y = 45 * 20 * x * y = 900 * x * y.