Given the inequality:
$$5 x + 2 < 0$$
To solve this inequality, we must first solve the corresponding equation:
$$5 x + 2 = 0$$
Solve:
Given the linear equation:
5*x+8/4 = 0
Move free summands (without x)
from left part to right part, we given:
$$5 x = -2$$
Divide both parts of the equation by 5
x = -2 / (5)
$$x_{1} = - \frac{2}{5}$$
$$x_{1} = - \frac{2}{5}$$
This roots
$$x_{1} = - \frac{2}{5}$$
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
$$x_{0} = x_{1} - \frac{1}{10}$$
=
$$- \frac{2}{5} + - \frac{1}{10}$$
=
$$- \frac{1}{2}$$
substitute to the expression
$$5 x + 2 < 0$$
$$\frac{\left(-1\right) 5}{2} + 2 < 0$$
-1/2 < 0
the solution of our inequality is:
$$x < - \frac{2}{5}$$
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