Factor the expression.?

👨🏻‍🏫 學術台數學

[匿名]

2009-11-29 10:06 am

x^2 + 10x + 21 =

回答 (6)

An ESL Learner

2009-11-29 10:19 am

✔ 最佳答案

x^2 + 10x + 21
= x^2 + 3x + 7x + 21
= (x^2 + 3x) + (7x + 21)
= x(x + 3) + 7(x + 3)
= (x + 3)(x + 7)

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Engr. Ronald

2009-11-29 6:41 pm

x^2 + 10x + 21 = (x+7)(x+3) answer//

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[匿名]

2009-11-29 6:21 pm

x^2 + 10x + 21 = x2 + 7x + 3x + 21
. . . . . . . . . . . = x(x + 7) + 3(x + 7)
. . . . . . . . . . . = (x + 3)(x + 7) ....................... Answer

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[匿名]

2009-11-29 6:15 pm

(x+7)(x+3) = 0

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[匿名]

2009-11-29 6:14 pm

(x+7)(x+3)
because 3 times 7 is 21 and 3 plus 7 is ten

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[匿名]

2009-11-29 6:13 pm

xÂ² + 10x + 21 = (x + 3)(x + 7)

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