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Please help me I’ve got to get this done!

Please help me I’ve got to get this done!-example-1
User Cphilpot
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1 Answer

9 votes

Answer:

(
2x + 3)^(2)

Explanation:


f(x) = 4x^(2) + 12x + 9

Factor the expression by grouping. First, the expression needs to be rewritten
4x^(2) + ax + bx + 9. To find a and b, set up a system to be solved.


a + b = 12\\ab = 4 x 9 = 36

Since ab is positive, a and b have the same sign. Since a+b is positive, a and b are both positive. List all such integer pairs that give product 36.

1,36

2,18

3,12

4,9

6,6

Calculate the sum for each pair.

1 + 36 = 37

2 + 18 = 20

3 + 12 = 15

4 + 9 = 13

6 + 6 = 12

The solution is the pair that gives sum 12.

a=6

b=6

Rewrite
4x^(2) + 12x + 9 as
(4x^(2) + 6x) + (6x + 9)


(4x^(2) + 6x) + (6x + 9)

Factor out 2x in the first and 3 in the second group.


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

Factor out the common term 2x + 3 by using the distributive property.


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

Rewrite as a binomial square.


(2x + 3)^(2)

Hope it helps and have a great day! =D

~sunshine~

User RMu
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3.7k points