Given the inequality:
$$3 x + 1 > -1$$
To solve this inequality, we must first solve the corresponding equation:
$$3 x + 1 = -1$$
Solve:
Given the linear equation:
3*x+1 = -1
Move free summands (without x)
from left part to right part, we given:
$$3 x = -2$$
Divide both parts of the equation by 3
x = -2 / (3)
$$x_{1} = - \frac{2}{3}$$
$$x_{1} = - \frac{2}{3}$$
This roots
$$x_{1} = - \frac{2}{3}$$
is the points with change the sign of the inequality expression.
First define with the sign to the leftmost point:
$$x_{0} < x_{1}$$
For example, let's take the point
$$x_{0} = x_{1} - \frac{1}{10}$$
=
$$- \frac{2}{3} + - \frac{1}{10}$$
=
$$- \frac{23}{30}$$
substitute to the expression
$$3 x + 1 > -1$$
$$\frac{\left(-23\right) 3}{30} + 1 > -1$$
-13
---- > -1
10
Then
$$x < - \frac{2}{3}$$
no execute
the solution of our inequality is:
$$x > - \frac{2}{3}$$
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