How do you factor #2x^2-x-3#?

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Answer 1 · 2017-07-11T14:45:58

#(2x-3)(x+1)#

#2x^2-x-3=(2x-3)(x+1)#

since it is #2x^2#
in one of the brackets there must be a #x# with the coefficient 2
#(2x...)(x...)#

next think how 3, 2, 1 (coefficients of #x^2,x and x^0# respectively) relate to each other (using addition and subtraction)
#3-2=1#

what makes 3 and 2 and 1? using multiplication
#3*1=3#
#2*1=2#

Now we have clearer idea on what to do
#(2x-3)(x+1)#
there you go

If you are having difficulties to factorise (provided that the equation is factorisable), don't frustrate. You just need more practices.

Answer 2 · 2017-07-11T14:47:35

#(x + 1)(2x - 3)#

#2x^2 - x - 3#

#= 2x^2 - 3x + 2x - 3#

#= x(2x - 3) +1(2x - 3)#

#= (x + 1)(2x - 3)#