a) 9x - [4x - (4 + x)] = 4x - 2 9x - (4x - 4 - x) = 4x - 2 9x - 4x + 4 + x = 4x - 2 6x + 4 = 4x - 2 | - 4x 2x + 4 = - 2 | - 4 2x = - 6 | : 2 x = - 3 b) 13 + [5u - (7u + 9) + 12u] - 15 = 9 13 + 5u - 7u - 9 + 12 - 15 = 9 1 - 2u = 9 | - 1 - 2u = 8 | * (-1) 2u = -8 | : 2 u = - 4 c) 13 - 4w - [47 - (41 - 7w)] = 3w 13 - 4w - (47 - 41 + 7w) = 3w 13 - 4w - 47 + 41 - 7w = 3w 7 - 11w = 3w | + 11w 7 = 14w | : 14 7/14 = w 1/2 = w d) 1,2 = 5,7 - [7,6x - (1,2x - 6,9)] 1,2 = 5,7 - (7,6x - 1,2x + 6,9) 1,2 = 5,7 - 7,6x + 1,2x - 6,9 1,2 = - 1,2 - 6,4x | + 1,2 2,4 = - 6,4x | * (-10) - 24 = 64x | : 64 - 24/64 = x - 1/8 = x
Rozwiązanie w załączniku :)