How do you factor the expression #3x^2 + 10x - 8#?

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Answer 1 · 2016-03-05T17:02:52

# (3x-2) (x+4) # is the factorised form of the expression.

#3x^2 +10x-8#

We can Split the Middle Term of this expression to factorise it.

In this technique, if we have to factorise an expression like #ax^2 + bx + c#, we need to think of 2 numbers such that:

#N_1*N_2 = a*c = 3*-8 = -24#

AND

#N_1 +N_2 = b = 10#

After trying out a few numbers we get #N_1 = 12# and #N_2 =-2#

#12*-2 = -24#, and #12+(-2)= 10#

#3x^2 +10x-8 =3x^2 +12x -2x-8#

# = 3x (x+4) -2 (x+4)#

# = (3x-2) (x+4) #

# (3x-2) (x+4) # is the factorised form of the expression.