How do you factor $7 a^{3} - 21 a^{2}$ $7a^3 - 21a^2$ ?

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Answer 1 · 2016-12-22T15:22:56

$7 a^{2} (a - 3)$ $7a^2 (a - 3)$

$7 a^{3} - 21 a^{2}$ $7a^3 - 21a^2$

= $7 . a . a . a - 7.3 . a . a$ $7.a.a.a - 7.3.a.a$

= 7.a.a (a - 3)

= $7 a^{2} (a - 3)$ $7a^2 (a-3)$

How do you factor 7a3−21a27a^3 - 21a^2?