Question

12x²-x-35


plz tell me with explainaton I will mark as brainlist​

Answer 1

Step-1 : Multiply the coefficient of the first term by the constant 12 • -35 = -420

Step-2 : Find two factors of -420 whose sum equals the coefficient of the middle term, which is -1 .

-420 + 1 = -419

-210 + 2 = -208

-140 + 3 = -137

-105 + 4 = -101

-84 + 5 = -79

-70 + 6 = -64

-60 + 7 = -53

-42 + 10 = -32

-35 + 12 = -23

-30 + 14 = -16

-28 + 15 = -13

-21 + 20 = -1

That's it

Step-3 : Rewrite the polynomial splitting the middle term using the two factors found in step 2 above, -21 and 20

12x2 - 21x + 20x - 35

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

3x • (4x-7)

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

5 • (4x-7)

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

(3x+5) • (4x-7)

Which is the desired factorization

Final result : (4x - 7) • (3x + 5)