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What is the answer to this question

What is the answer to this question-example-1
User Sudhakar Kalmari
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1 Answer

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13 votes

Explanation:

what is the question ?

solve it for x ?

if that is the case :

-9/(x+4) - 2/(x²+4x) = -4

-9 - 2(x+4)/(x²+4x) = -4(x+4)

-9 - 2(x+4)/(x(x+4)) = -4(x+4)

-9 - 2/x = -4(x+4)

-9x - 2 = -4x(x+4)

-9x - 2 = -4x² - 16x

-2 = -4x² - 7x

0 = -4x² - 7x + 2

the general solution to such a quadratic equation is

x = (-b ± sqrt(b² - 4ac))/(2a)

in our case

a = -4

b = -7

c = 2

so

x = (7 ± sqrt((-7)² - 4×-4×2))/(2×-4) =

= (7 ± sqrt(49 + 32))/(-8) = (7 ± sqrt(81))/(-8) =

= (7 ± 9)/(-8)

x1 = (7+9)/(-8) = 16/-8 = -2

x2 = (7-9)/(-8) = -2/-8 = 1/4 = 0.25

x1 and x2 are the two solutions to this equation.

User Omar Elabd
by
3.1k points