The correct answer is: [B]: " a - 2b + 3c " .
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We have a "numerator"; which is: " (5ab - 10b ^2 + 15bc)" ; and
a "denominator" ; which is: "5b" ;
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Note: The denominator cannot equal "0" (zero) ; since one cannot divide by "0"; as such, "5b ≠ 0" ; and as such: "b ≠ 0" ;
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We can factor a "5b" out of the numerator, and then "cancel out" that "5b" in the numerator" with that "5b" in the "denominator"; to "1" ; since "5b" divided by "5b" = 1; (since anything divided by that same value equals "1"; and then eliminate the denominator, which is "1"; since the numerator, divided by "1", is: "the numerator" (since anything divided by "1" equals that same value.
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So, given the numerator: "(5ab - 10b² + 15bc)" ;
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→ Factor out a "5b" ;
→ 5b (a - 2b + 3c) ; and rewrite the expression as:
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→ {5b (a - 2b + 3c) } / {5b} ; Then cancel out the "5b" in both the numerator and the denominator;
→ and we are left with: " a - 2b + 3c " ; which is: Answer choice: [B].
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