lillyana0
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PLEASE HELP (30 POINTS) Solve the rational equation x/3 = x^2/x + 5 , and check for extraneous solutions.

A. x = 0; x = -5/2 is an extraneous solution
B. x = 5/2; x = 0 is an extraneous solution
C. x = 0 and x = 5/2
D. x = 0 and x = -5/2

Answer :

Option C: [tex]x=0[/tex] and [tex]x=\frac{5}{2}[/tex] are the solutions.

Explanation:

The equation is [tex]\frac{x}{3} =\frac{x^{2} }{x+5}[/tex]

We shall determine the value of x, by simplifying the equation.

[tex]$\begin{aligned} x(x+5) &=3 x^{2} \\ x^{2}+5 x &=3 x^{2} \\ 2 x^{2}-5 x &=0 \\ x(2 x-5) &=0 \end{aligned}$[/tex]

Thus, [tex]x=0[/tex] and [tex]x=\frac{5}{2}[/tex] are the solutions.

Now, let us check whether the solutions are extraneous solutions.

Let us substitute [tex]x=0[/tex] in the original equation to check whether both sides of the equation are equal.

[tex]\begin{aligned}&\frac{0}{3}=\frac{0^{2}}{0+5}\\&0=\frac{0}{5}\\&0=0\end{aligned}[/tex]

Thus, both sides of the equation are equal.

Hence [tex]x=0[/tex] is a true solution.

Now, Let us substitute [tex]x=\frac{5}{2}[/tex] in the original equation to check whether both sides of the equation are equal.

[tex]\begin{aligned}\frac{\left(\frac{5}{2}\right)}{3} &=\frac{\left(\frac{5}{2}\right)^{2}}{\left(\frac{5}{2}\right)+5} \\\frac{5}{6} &=\frac{\left(\frac{25}{4}\right)}{\left(\frac{15}{2}\right)} \\\frac{5}{6} &=\frac{5}{6}\end{aligned}[/tex]

Thus, both sides of the equation are equal.

Hence, [tex]x=\frac{5}{2}[/tex] is a true solution.

Thus, solutions are not extraneous.

Hence, Option C is the correct answer.

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