a) 5х – 3 + (8х – 7) = 5х – 3 + 8х – 7 = (5x + 8x) + (–3 – 7) = 13x – 10
б) 6х – 7 – (4х – 8) = 6х – 7 – 4х + 8 = (6x – 4x) + (–7 + 8) = 2x + 1
a) 5х – 3 + (8х – 7) = 5х – 3 + 8х – 7 = (5x + 8x) + (–3 – 7) = 13x – 10
б) 6х – 7 – (4х – 8) = 6х – 7 – 4х + 8 = (6x – 4x) + (–7 + 8) = 2x + 1