How do you factor 3x^2 +10x - 8?
2 Answers
Explanation:
first multiply
then find two numbers that if we add or subtract we get
and the numbers are
then we place those numbers as follow :-
then we group them
now take the common factor out.
then group the numbers outside of the brackets
and that is the answer
Proper Solution:-
Explanation:
"for a quadratic in "color(blue)"standard form"
•color(white)(x)ax^2+bx+c ;a!=0
"consider the factors of the product ac which sum to b"
3x^2+10x-8larrcolor(blue)"is in standard form"
"with "a=3,b=10" and "c=-8
"consider factors of "3xx-8=-24" which sum to + 10"
"the required factors are "+12" and "-2
color(blue)"split the middle term using these factors"
3x^2+12x-2x-8larrcolor(blue)"factor by grouping"
=color(red)(3x)(x+4)color(red)(-2)(x+4)
"take out the common factor "(x+4)
=(x+4)(color(red)(3x-2))
rArr3x^2+10x-8=(x+4)(3x-2)