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To solve the equation x + x + x + 91 = -2, we can combine like terms:

3x + 91 = -2

Next, we can isolate the variable by subtracting 91 from both sides:

3x = -2 - 91

3x = -93

Dividing both sides by 3, we get:

x = -93/3

Simplifying, we find:

x = -31

Now, let's solve the equation x + x + x + 82 = -2 - x:

3x + 82 = -2 - x

Adding x to both sides:

4x + 82 = -2

Subtracting 82 from both sides:

4x = -2 - 82

4x = -84

Dividing both sides by 4:

x = -84/4

Simplifying, we find:

x = -21

Next, let's solve the equation (5x + 1)^2 = 121:

Taking the square root of both sides:

5x + 1 = ±√121

Simplifying the square root:

5x + 1 = ±11

For the positive square root:

5x + 1 = 11

Subtracting 1 from both sides:

5x = 10

Dividing both sides by 5:

x = 2

For the negative square root:

5x + 1 = -11

Subtracting 1 from both sides:

5x = -12

Dividing both sides by 5:

x = -12/5

So the solutions to the equation (5x + 1)^2 = 121 are x = 2 and x = -12/5.