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2x-1:5-x>_0 inequation

A inequation with variable

The solution

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2*x - 1/5 - x >= 0
$$- x + \left(2 x - \frac{1}{5}\right) \geq 0$$
-x + 2*x - 1/5 >= 0
Detail solution
Given the inequality:
$$- x + \left(2 x - \frac{1}{5}\right) \geq 0$$
To solve this inequality, we must first solve the corresponding equation:
$$- x + \left(2 x - \frac{1}{5}\right) = 0$$
Solve:
Given the linear equation:
2*x-1/5-x = 0

Looking for similar summands in the left part:
-1/5 + x = 0

Move free summands (without x)
from left part to right part, we given:
$$x = \frac{1}{5}$$
$$x_{1} = \frac{1}{5}$$
$$x_{1} = \frac{1}{5}$$
This roots
$$x_{1} = \frac{1}{5}$$
is the points with change the sign of the inequality expression.
First define with the sign to the leftmost point:
$$x_{0} \leq x_{1}$$
For example, let's take the point
$$x_{0} = x_{1} - \frac{1}{10}$$
=
$$- \frac{1}{10} + \frac{1}{5}$$
=
$$\frac{1}{10}$$
substitute to the expression
$$- x + \left(2 x - \frac{1}{5}\right) \geq 0$$
$$- \frac{1}{10} + \left(- \frac{1}{5} + \frac{2}{10}\right) \geq 0$$
-1/10 >= 0

but
-1/10 < 0

Then
$$x \leq \frac{1}{5}$$
no execute
the solution of our inequality is:
$$x \geq \frac{1}{5}$$
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Solving inequality on a graph
Rapid solution [src]
And(1/5 <= x, x < oo)
$$\frac{1}{5} \leq x \wedge x < \infty$$
(1/5 <= x)∧(x < oo)
Rapid solution 2 [src]
[1/5, oo)
$$x\ in\ \left[\frac{1}{5}, \infty\right)$$
x in Interval(1/5, oo)