Question

Factorise by using splitting the middle term
4x²+x–18

Answer 1

Answer:

Step-by-step explanation:

$4x^{2}$+x-18

sum=1

product=-72

$4x^{2}$-8x+9x-18

4x(x-2)+9(x-2)

(x-2)(4x+9)

STAY SAFE !!!!

Answer 2

Step by Step Solution:

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STEP

1

:

Equation at the end of step 1

 (22x2 -  x) -  18

STEP

2

:

Trying to factor by splitting the middle term

2.1     Factoring  4x2-x-18  

The first term is,  4x2  its coefficient is  4 .

The middle term is,  -x  its coefficient is  -1 .

The last term, "the constant", is  -18  

Step-1 : Multiply the coefficient of the first term by the constant   4 • -18 = -72  

Step-2 : Find two factors of  -72  whose sum equals the coefficient of the middle term, which is   -1 .

     -72    +    1    =    -71  

     -36    +    2    =    -34  

     -24    +    3    =    -21  

     -18    +    4    =    -14  

     -12    +    6    =    -6  

     -9    +    8    =    -1    That's it

Step-3 : Rewrite the polynomial splitting the middle term using the two factors found in step 2 above,  -9  and  8  

                    4x2 - 9x + 8x - 18

Step-4 : Add up the first 2 terms, pulling out like factors :

                   x • (4x-9)

             Add up the last 2 terms, pulling out common factors :

                   2 • (4x-9)

Step-5 : Add up the four terms of step 4 :

                   (x+2)  •  (4x-9)

            Which is the desired factorization

Final result :

 (4x - 9) • (x + 2)