Answer:
(a) i and ii: 2b-2 = b+b-2
(b) i and iii: c+d = d+c
(c) ii and iii: a + 2b - 1 = a+b-1+b
(d) i and iii: x+(y-z) = x-(z-y)
(e) ii and iii: (a-1)² = (1-a)²
(f) i and ii: 3a-b-1-1 = 3a+b-2-2b
Explanation:
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