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?
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
:)
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))
To divide a fraction by -1, you simply multiply the numerator and denominator of the fraction by -1. This will flip the sign of both the numerator and denominator, effectively changing the division to multiplication.
So, considering the fraction 2 - x, when divided by -1, it becomes (-1)(2 - x) / (-1) = (x - 2) / 1 = x - 2.
Therefore, after dividing 2 - x by -1, the fraction becomes x - 2. The subtraction sign in front of it does not change to an addition sign.