The distributive property: a(b + c) = ab + ac
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Factors of 56: 1, 2, 4, 7, 8, 14, 28, 56
Factors of 64: 1, 2, 4, 8, 16, 32, 64
GCF(56, 64) = 8
56 = 8 · 7
64 = 8 · 8
56 + 64 = 8 · 7 + 8 · 8 = = 8(7 + 8)
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Factors of 30: 1, 2, 3, 5, 6, 10, 15, 30
Factors of 54: 1, 2, 3, 6, 9, 18, 27, 54
GCF(30, 54) = 6
30 = 6 · 5
54 = 6 · 9
30 + 54 = 6 · 5 + 6 · 9 = 6(5 + 9)