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10 POINTS!! PLEASE HELP!!

10 POINTS!! PLEASE HELP!!-example-1

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Answer:

only the third answer is right.

Explanation:

to solve it, we need to bring everything to the same denominator (the expression below the division line) or eliminate it completely.

how do we do it ? by multiplying everything with the same expression, so that we can eliminate the denominator for every term.

when looking for the best option I see that

(x² + 5x + 6) = (x + 2)×(x + 3)

that is great, because this covers all 3 denominators in our main expression.

so, we multiply everything by ((x+2)×(x+3)) and eliminate the denominators and the corresponding part of our multiplier.

that leaves us with

x×(x+3) + 2 = 5×(x+2)

now we simply simplify the expression

x² + 3x + 2 = 5x + 10

x² - 8x - 8 = 0

a squared equation has typically 2 solutions. and they are defined as

x = (-b ± sqrt(b² - 4ac)) / (2a)

in our case

a = 1

b = -8

c = -8

x = (8 ± sqrt(64 + 32)) / 2 = (8 ± sqrt(96))/2 =

= (8 ± sqrt(16×6))/2 = (8 ± 4×sqrt(6))/2 = 4 ± 2×sqrt(6)

x1 = 4 + 2×sqrt(6)

x2 = 4 - 2×sqrt(6)

both solutions are different from -2 or -3, therefore -2 and -3 are not solutions at all, and they cannot be extraneous solutions either for that reason.

and since we have 2 perfectly fine solutions, the answer options work no or only one solutions are wrong too.

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