Question

factor.
3x^2-5x-12

Answer 1

(x-3)(x+(4/3))

Answer 2

??

Answer 3

(3x-4 )(x+3 )

Answer 4

can you explain the steps..

Answer 5

sir actually what we get after factorising are the two roots of the equation( those values of x which makes the value of function equal to zero), so our objective to factorise is indirrectly to find the roots of the equation . u following till now?

Answer 6

there is a formula for finding the roots of a quadratic equation, use that to get the roots of this equation.
suppose the roots come to be
x=h nd x=j, then the equation will be, (x-h)(x-j) :)

Answer 7

yeah I know how to factor normal ones, but this one is complicated. you have to find two numbers that multiply to c and add to b, but for this one, it's a little different.

Answer 8

the quadratic formula is a fool proof way to factorise( also know as shri dharacharya formula, given by an indian):) u know the formula right?

Answer 9

try to find those 2no. which has a product=3*12=36, and have a difference between them=5.
we have,
36=1*36
36=2*18
36=3*12
36=4*9 ----------->here, we have a difference of 5 between the no.(irrespective of signs)

3x2−5x−12

3x2−9x+4x−12
(writing -5 as sum of -9 and 4)
Take out common value from any two groups
[3x2−9x][+4x−12]


3x(x−3)3(+x−3)


=
(3x+3)(x−3)