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16 votes
16 votes
Factor the following polynomial 9x2 + 21x – 18

User Jari
by
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2 Answers

12 votes
12 votes

Answer:

factors are

21 and x

Explanation:

equation 9 × 2 + 21x - 18

terms 9 , 2, 21x, -18

factors 21x = 21 and x

User Dull Bananas
by
3.0k points
28 votes
28 votes

Answer:

3(x + 3)(3x - 2)

Explanation:

Given

9x² + 21x - 18 ← factor out 3 from each term

= 3(3x² + 7x - 6) ← factor the quadratic

Consider the factors of the product of the x² term and the constant term which sum to give the coefficient of the x- term

product = 3 × - 6 = - 18 and sum = + 7

The factors are + 9 and - 2

Use these factors to split the x- term

3x² + 9x - 2x - 6 ( factor first/second and third/fourth terms )

3x(x + 3) - 2(x + 3) ← factor out (x + 3) from each term

(x + 3)(3x - 2)

Then

9x² + 21x - 18 = 3(x + 3)(3x - 2) ← in factored form

User Adrian Ber
by
2.7k points