ugh sorry the formatting is so bad, it got rid of my spaces. hopefully people can answer based on my little blurb at the end
:)
i dont need the answer for this, I just need to know one thing...
but first here is the question:
3x + 5 x + 1 4x^2 - 3x - 1
--------- - -------- - -----------------
x + 5 2 - x (x + 5)(x-2)
I know the common denominator is (x+5)(x-2). But, as you can see, 2 - x needs to be divided by -1. What would that fraction look like after it has been divided by -1, and would it change the subtraction sign in front of it to an addition sign?
2 answers
you got the LCD right. But when adding fractions, you need to adjust the numerators accordingly.
2/3 - 4/7 = (2*7 - 4*3)/(3*7)
So your fractions add up as
[(3x+5)(x-2) - (x+1)(x+5) - (4x^2-3x-1)]/((x+5)(x-2))
= -2(x^2+2x+7)/((x+5)(x-2))
2/3 - 4/7 = (2*7 - 4*3)/(3*7)
So your fractions add up as
[(3x+5)(x-2) - (x+1)(x+5) - (4x^2-3x-1)]/((x+5)(x-2))
= -2(x^2+2x+7)/((x+5)(x-2))