Determine for what values of $x$ the expressions $2x + 2$,$x + 4$, $x + 2$ can represent the sidelengths of a right triangle.
To determine for what values of \( x \) the expressions \( 2x + 2 \), \( x + 4 \), and \( x + 2 \) can represent the side lengths of a right triangle, we need to use the Pythagorean theorem. The Pythagorean theorem states that for a right triangle with side lengths \( a \), \( b \), and hypotenuse \( c \), the following equation holds:
\[ a^2 + b^2 = c^2 \]

We will consider two cases: one where \( 2x + 2 \) is the hypotenuse and another where \( x + 4 \) is the hypotenuse.

### Case 1: \( 2x + 2 \) is the hypotenuse
In this case, we assume \( 2x + 2 \) is the hypotenuse, and the other two sides are \( x + 4 \) and \( x + 2 \). Therefore, we have:
\[ (x + 4)^2 + (x + 2)^2 = (2x + 2)^2 \]

Expanding and simplifying:
\[ (x + 4)^2 = x^2 + 8x + 16 \]
\[ (x + 2)^2 = x^2 + 4x + 4 \]
\[ (2x + 2)^2 = 4x^2 + 8x + 4 \]

Substituting these into the Pythagorean theorem:
\[ x^2 + 8x + 16 + x^2 + 4x + 4 = 4x^2 + 8x + 4 \]
\[ 2x^2 + 12x + 20 = 4x^2 + 8x + 4 \]

Rearranging terms to one side:
\[ 2x^2 + 12x + 20 - 4x^2 - 8x - 4 = 0 \]
\[ -2x^2 + 4x + 16 = 0 \]
\[ 2x^2 - 4x - 16 = 0 \]

Dividing the entire equation by 2:
\[ x^2 - 2x - 8 = 0 \]

Factoring the quadratic equation:
\[ (x - 4)(x + 2) = 0 \]

Thus, the solutions are:
\[ x = 4 \quad \text{or} \quad x = -2 \]

Since side lengths must be positive, we discard \( x = -2 \). Therefore, \( x = 4 \).

### Case 2: \( x + 4 \) is the hypotenuse
In this case, we assume \( x + 4 \) is the hypotenuse, and the other two sides are \( 2x + 2 \) and \( x + 2 \). Therefore, we have:
\[ (2x + 2)^2 + (x + 2)^2 = (x + 4)^2 \]

Expanding and simplifying:
\[ (2x + 2)^2 = 4x^2 + 8x + 4 \]
\[ (x + 2)^2 = x^2 + 4x + 4 \]
\[ (x + 4)^2 = x^2 + 8x + 16 \]

Substituting these into the Pythagorean theorem:
\[ 4x^2 + 8x + 4 + x^2 + 4x + 4 = x^2 + 8x + 16 \]
\[ 5x^2 + 12x + 8 = x^2 + 8x + 16 \]

Rearranging terms to one side:
\[ 5x^2 + 12x + 8 - x^2 - 8x - 16 = 0 \]
\[ 4x^2 + 4x - 8 = 0 \]

Dividing the entire equation by 4:
\[ x^2 + x - 2 = 0 \]

Factoring the quadratic equation:
\[ (x - 1)(x + 2) = 0 \]

Thus, the solutions are:
\[ x = 1 \quad \text{or} \quad x = -2 \]

Since side lengths must be positive, we discard \( x = -2 \). Therefore, \( x = 1 \).

### Conclusion
The values of \( x \) for which \( 2x + 2 \), \( x + 4 \), and \( x + 2 \) can represent the side lengths of a right triangle are \( x = 4 \) and \( x = 1 \).

The final answer is \( \boxed{ x = 4 } \) and \( x = 1 \)