49,020 views
0 votes
0 votes
Simplify the expression (Image below) Precalculus please help! D:

Simplify the expression (Image below) Precalculus please help! D:-example-1
User Bossi
by
2.0k points

1 Answer

26 votes
26 votes

Answer:


\boxed{\sf (x-4)/(x^2-2x) }

Explanation:


\sf \cfrac{x+6}{x^2+3x}-\cfrac{5}{x^2+x-6}

Factor x² + 3x, and x²+ x - 6


\sf \cfrac{x+6}{x(x+3)} -\cfrac{5}{(x-2)(x+3}

To add or subtract expressions, we expand them to make their denominators the same, LCM of x(x+3) and (x-2)(x+3) is x(x-2) (x+3).

Multiply
\sf (x+6)/(x(x+3))* \sf (x-3)/(x-2) and
(5)/((x-2)(x+3)) * (x)/(x)


\sf \cfrac{(x+6)(x-2)}{x(x-2)(x+3)}-\cfrac{5x}{x(x-2)(x+3)}

Here,
\sf ((x+6)(x-2))/(x(x-2)(x+3)) and
\sf (5x)/(x(x-2)(x+3) have the same denominators, we will subtract them by subtracting their numerators:


\sf \cfrac{(x+6)(x-2)-5x}{x(x-2)(x+3)}

*Multiply (x+6)(x-2)-5x:


\sf \cfrac{x^2-2x+6x-12-5x}{x(x-2)(x+3)}

Combine like terms: x² - 2x + 6x - 12 - 5x


\sf \cfrac{-x-12+x^2}{x(x-2)(x+3)}

Now, factor expressions that are not already factored:


\sf \cfrac{(x-4)(x+3)}{x(x-2)(x+3)}


\sf \cfrac{x-4}{x(x-2)}

Expand:


\sf \cfrac{x-4}{x^2-2x}

__________________________

User Jorawar Singh
by
3.4k points