Question

Difficulty: MediumRadical and Rational Equations

What is the larger solution to the equation below?

xx2+3x=2\frac{x}{x - 2} + \frac{3}{x} = 2

Answer: 6

Answer

The larger solution to the equation is 6.
To solve the rational equation, we clear the denominators by multiplying both sides by x(x2)x(x - 2), which yields the quadratic equation x27x+6=0x^2 - 7x + 6 = 0. Factoring this equation gives (x6)(x1)=0(x - 6)(x - 1) = 0, leading to the solutions x=6x = 6 and x=1x = 1. Both values are valid because they do not make any denominator of the original expression equal to zero. The larger of the two values is 6.

Step-by-Step Solution

1
Multiply both sides of the equation by the common denominator x(x2)x(x - 2) to clear the fractions.
x2+3(x2)=2x(x2)x^2 + 3(x - 2) = 2x(x - 2)
Clearing denominators simplifies the rational equation into a polynomial equation.
2
Expand both sides of the equation.
x2+3x6=2x24xx^2 + 3x - 6 = 2x^2 - 4x
Distributing the multiplication allows us to combine like terms.
3
Move all terms to one side of the equation to write it in the standard quadratic form ax2+bx+c=0ax^2 + bx + c = 0.
x27x+6=0x^2 - 7x + 6 = 0
Setting the quadratic expression to zero prepares it for factoring.
4
Factor the quadratic equation.
(x6)(x1)=0(x - 6)(x - 1) = 0
Finding two numbers that multiply to 66 and sum to 7-7 gives 6-6 and 1-1.
5
Identify the values of xx that satisfy the factored equation and check for extraneous solutions.
x=6x = 6 or x=1x = 1
Neither solution makes the denominators in the original equation, x2x-2 or xx, equal to zero, so both are valid. The larger of these two solutions is 6.

Key Concept

Solving rational equations by clearing denominators to form a quadratic equation, and verifying solutions against the domain constraints.
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