Solve for x: 2 over quantity x minus 2 plus 7 over quantity x squared minus 4 equals 5 over x.
x = negative 4 over 3 and x = −5
x = negative 4 over 3 and x = 5
x = 4 over 3 and x = −5
x = 4 over 3 and x = 5

Solve for x 2 over quantity x minus 2 plus 7 over quantity x squared minus 4 equals 5 over x x negative 4 over 3 and x 5 x negative 4 over 3 and x 5 x 4 over 3 class=

Respuesta :

 x = negative 4 over 3 and x = 5

which is also B


we have

[tex]\frac{2}{x-2}+ \frac{7}{x^{2}-4}= \frac{5}{x}[/tex]

Remember that

[tex]x^{2}-4=(x+2)(x-2)[/tex]

Multiply by [tex][x(x^{2} -4)][/tex] both sides

[tex][x(x^{2} -4)]\frac{2}{x-2}+[x(x^{2} -4)]\frac{7}{x^{2}-4}= [x(x^{2} -4)]\frac{5}{x}[/tex]

Simplify

[tex]2x(x+2)+7x=5(x^{2}-4) \\ \\2x^{2}+4x+7x=5 x^{2}-20 \\ \\3x^{2}-11x-20=0[/tex]

The formula to solve a quadratic equation of the form [tex]ax^{2} +bx+c=0[/tex] is equal to

[tex]x=\frac{-b(+/-)\sqrt{b^{2}-4ac}} {2a}[/tex]

in this problem we have

[tex]3x^{2} -11x-20=0[/tex]  

so

[tex]a=3\\b=-11\\c=-20[/tex]

substitute in the formula

[tex]x=\frac{11(+/-)\sqrt{-11^{2}-4(3)(-20)}} {2*3}[/tex]

[tex]x=\frac{11(+/-)\sqrt{121+240}} {6}[/tex]

[tex]x=\frac{11(+/-)\sqrt{361}} {6}[/tex]

[tex]x=\frac{11(+/-)19}{6}[/tex]

[tex]x=\frac{11+19}{6}=5[/tex]

[tex]x=\frac{11-19}{6}=-\frac{4}{3} [/tex]

therefore

the answer is the option

x = negative 4 over 3 and x = 5