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1 = 20 / x ² - 8 / x . What are the steps needed to get the answers 2 and 10 and is one of the answers negative?

2007-05-06 09:44:53 · 5 answers · asked by Maime 1 in Science & Mathematics Mathematics

5 answers

You asked twice. :-)

Multiply the second fraction by x²/x² to get a common denominator. 20/x² - 8x/x² = 1 or (20-8x)/x² = 1.

Multiply every term by x² and you get 20-8x = x².

So you need to solve x² +8x -20 = 0. You can factor this as (x+10)(x-2) = 0 so your solutions are x = -10 or x = 2.

Enjoy!

2007-05-06 09:51:10 · answer #1 · answered by Anonymous · 0 0

first you would multiply both sides of the equation by the greatest common denominator which is (x^2).
1(x^2)= 20/x^2(x^2) - 8/x(x^2)
the x^2 and the one in the 20/x^2 would cancel out and the x in 8/x goes into x^2 once. so you would get:
x^2=20-8x
bring all the numbers to one side of the equation by subtracting 20 and adding 8x.
x^2+8x-20=0
solve by factoring
(x+10)(x-2)=0
solve for x
x+10=0
subtract 10
x-2=0
add 2
x=-10 x=2 are the answers.

2007-05-06 10:01:38 · answer #2 · answered by Anonymous · 0 0

1 = 20 / (x^2) - 8 / x
The LCD of this equation is x^2. Multiply each term on both sides of the equation by x^2.

(x^2)(1) = (x^2)(20) / (x^2) - (x^2)(8) / x
x^2 = 20 - 8x

Rewrite the quadratic equation in standard form.

x^2 +8x - 20 = 0
(x + 10)(x - 2) = 0
x + 10 = 0 or x - 2 = 0
x = -10 or x = 2

2007-05-06 09:56:53 · answer #3 · answered by mathjoe 3 · 0 0

x² = 20 - 8x
x² + 8x - 20 = 0
(x + 10).(x - 2) = 0
x = - 10, x = 2

2007-05-06 10:24:20 · answer #4 · answered by Como 7 · 0 0

1=(20-8x)/x²
x²=20-8x
x²+8x-20=0
(x+10)(x-2)=0
x=-10,2

hope this helped u.

2007-05-06 09:49:49 · answer #5 · answered by Anonymous · 0 0

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