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11 votes
11 votes
What is the difference?
2x+5 3x+ 5 X+ 1
x² – 3x X² – 9x x²-g

What is the difference? 2x+5 3x+ 5 X+ 1 x² – 3x X² – 9x x²-g-example-1
User Grace Note
by
2.4k points

1 Answer

18 votes
18 votes

Answer:

(x + 5)(x + 2) / (x³ - 9x)

Explanation:

We need to find a common denominator.

factor each denominator

x² - 3x = x(x - 3)

x³ - 9x = x(x² - 9) = x(x + 3)(x - 3)

x² - 9 = (x + 3)(x - 3)

As the factors of the first and third denominators are subsets of the second, the second is the LCD. This immediately eliminates the last two options as possible solutions.

Now we multiply each term by the missing factor over itself (1)

(2x + 5)(x + 3) - (3x + 5) - (x + 1)(x)]

(x² - 3x)(x + 3) (x³ - 9x) (x² - 9)(x)

[(2x² + 11x + 15) - (3x + 5) - (x² + x)] / (x³ - 9x)

[2x² + 11x + 15 - 3x - 5 - x² - x] / (x³ - 9x)

(x² + 7x + 10) / (x³ - 9x)

(x + 5)(x + 2) / (x³ - 9x)

User DolceVita
by
3.2k points
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