Solve 2x+2/x=4

$$2 x + \frac { 2 } { x } = 4$$

Solve for x

$$x=1$$

Steps Using Factoring By Grouping

Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by x.

$$2xx+2=4x$$

Multiply x and x to get x^{2}.

$$2x^{2}+2=4x$$

Subtract 4x from both sides.

$$2x^{2}+2-4x=0$$

Divide both sides by 2.

$$x^{2}+1-2x=0$$

Rearrange the polynomial to put it in standard form. Place the terms in order from highest to lowest power.

$$x^{2}-2x+1=0$$

To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as x^{2}+ax+bx+1. To find a and b, set up a system to be solved.

$$a+b=-2 ab=1\times 1=1$$

Since ab is positive, a and b have the same sign. Since a+b is negative, a and b are both negative. The only such pair is the system solution.

$$a=-1 b=-1$$

Rewrite x^{2}-2x+1 as \left(x^{2}-x\right)+\left(-x+1\right).

$$\left(x^{2}-x\right)+\left(-x+1\right)$$

Factor out x in the first and -1 in the second group.

$$x\left(x-1\right)-\left(x-1\right)$$

Factor out common term x-1 by using distributive property.

$$\left(x-1\right)\left(x-1\right)$$

Rewrite as a binomial square.

$$\left(x-1\right)^{2}$$

To find equation solution, solve x-1=0.

$$x=1$$

Steps Using the Quadratic Formula

Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by x.

$$2xx+2=4x$$

Multiply x and x to get x^{2}.

$$2x^{2}+2=4x$$

Subtract 4x from both sides.

$$2x^{2}+2-4x=0$$

All equations of the form ax^{2}+bx+c=0 can be solved using the quadratic formula: \frac{-b±\sqrt{b^{2}-4ac}}{2a}. The quadratic formula gives two solutions, one when ± is addition and one when it is subtraction.

$$2x^{2}-4x+2=0$$

This equation is in standard form: ax^{2}+bx+c=0. Substitute 2 for a, -4 for b, and 2 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.

$$x=\frac{-\left(-4\right)±\sqrt{\left(-4\right)^{2}-4\times 2\times 2}}{2\times 2}$$

Square -4.

$$x=\frac{-\left(-4\right)±\sqrt{16-4\times 2\times 2}}{2\times 2}$$

Multiply -4 times 2.

$$x=\frac{-\left(-4\right)±\sqrt{16-8\times 2}}{2\times 2}$$

Multiply -8 times 2.

$$x=\frac{-\left(-4\right)±\sqrt{16-16}}{2\times 2}$$

Add 16 to -16.

$$x=\frac{-\left(-4\right)±\sqrt{0}}{2\times 2}$$

Take the square root of 0.

$$x=-\frac{-4}{2\times 2}$$

The opposite of -4 is 4.

$$x=\frac{4}{2\times 2}$$

Multiply 2 times 2.

$$x=\frac{4}{4}$$

Divide 4 by 4.

$$x=1$$

Steps for Completing the Square

Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by x.

$$2xx+2=4x$$

Multiply x and x to get x^{2}.

$$2x^{2}+2=4x$$

Subtract 4x from both sides.

$$2x^{2}+2-4x=0$$

Subtract 2 from both sides. Anything subtracted from zero gives its negation.

$$2x^{2}-4x=-2$$

Divide both sides by 2.

$$\frac{2x^{2}-4x}{2}=-\frac{2}{2}$$

Dividing by 2 undoes the multiplication by 2.

$$x^{2}+\left(-\frac{4}{2}\right)x=-\frac{2}{2}$$

Divide -4 by 2.

$$x^{2}-2x=-\frac{2}{2}$$

Divide -2 by 2.

$$x^{2}-2x=-1$$

Divide -2, the coefficient of the x term, by 2 to get -1. Then add the square of -1 to both sides of the equation. This step makes the left hand side of the equation a perfect square.

$$x^{2}-2x+1=-1+1$$

Add -1 to 1.

$$x^{2}-2x+1=0$$

Factor x^{2}-2x+1. In general, when x^{2}+bx+c is a perfect square, it can always be factored as \left(x+\frac{b}{2}\right)^{2}.

$$\left(x-1\right)^{2}=0$$

Take the square root of both sides of the equation.

$$\sqrt{\left(x-1\right)^{2}}=\sqrt{0}$$

Simplify.

$$x-1=0 x-1=0$$

Add 1 to both sides of the equation.

$$x=1 x=1$$

The equation is now solved. Solutions are the same.

$$x=1$$