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Find the value of x if x, x+1 and x+2 are sides of a right triangle.

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We have the sides of a triangle: x, x+1, x+2.

The Pythagorean Theorem tells us that, in a right triangle, the following expression is true:

c^(2) = a^(2) + b^(2)

Let be the sides (legs of the triangle) x and x+1.

Then:

(x+2)^2 = x^(2) + (x+1)^2

We need to expand this:

x^(2) +4x + 4 = x^(2) + x^(2) +2x + 1

Rearrange the previous expression (grouping similar terms):

4x - 2x + 4 - 1 = 2x^(2) - x^(2)

2x + 3 = x^(2)

x^(2) - 2x - 3 = 0 [1]

Which is a quadratic equation. We need to find the values for this equation.

We can solve this equation using the quadratic formula and other methods.

One of the methods is as follows: we need to find two values that if we sum them, we obtain -2. If we multiply them, we obtain -3. Then, 1 -3 =-2 (-2x) and 1*(-3) = -3 (independent term).

The values for x are x = -1 or x = 3.

Since x = -1 is a negative number, it does not have sense. Therefore, the right value for x is 3 (x = 3).

The values for the sides of the right triangle are then:

x = 3, x+1 = 3+1 =4, x+2 = 3+2 =5 or

3, 4, 5.

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