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|2x-4|<5 inequation

A inequation with variable

The solution

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|2*x - 4| < 5
$$\left|{2 x - 4}\right| < 5$$
|2*x - 4| < 5
Detail solution
Given the inequality:
$$\left|{2 x - 4}\right| < 5$$
To solve this inequality, we must first solve the corresponding equation:
$$\left|{2 x - 4}\right| = 5$$
Solve:
For every modulo expressions in the equation
allow cases, when this expressions ">=0" or "<0",
solve the resulting equation.

1.
$$2 x - 4 \geq 0$$
or
$$2 \leq x \wedge x < \infty$$
we get the equation
$$\left(2 x - 4\right) - 5 = 0$$
after simplifying we get
$$2 x - 9 = 0$$
the solution in this interval:
$$x_{1} = \frac{9}{2}$$

2.
$$2 x - 4 < 0$$
or
$$-\infty < x \wedge x < 2$$
we get the equation
$$\left(4 - 2 x\right) - 5 = 0$$
after simplifying we get
$$- 2 x - 1 = 0$$
the solution in this interval:
$$x_{2} = - \frac{1}{2}$$


$$x_{1} = \frac{9}{2}$$
$$x_{2} = - \frac{1}{2}$$
$$x_{1} = \frac{9}{2}$$
$$x_{2} = - \frac{1}{2}$$
This roots
$$x_{2} = - \frac{1}{2}$$
$$x_{1} = \frac{9}{2}$$
is the points with change the sign of the inequality expression.
First define with the sign to the leftmost point:
$$x_{0} < x_{2}$$
For example, let's take the point
$$x_{0} = x_{2} - \frac{1}{10}$$
=
$$- \frac{1}{2} + - \frac{1}{10}$$
=
$$- \frac{3}{5}$$
substitute to the expression
$$\left|{2 x - 4}\right| < 5$$
$$\left|{-4 + \frac{\left(-3\right) 2}{5}}\right| < 5$$
26/5 < 5

but
26/5 > 5

Then
$$x < - \frac{1}{2}$$
no execute
one of the solutions of our inequality is:
$$x > - \frac{1}{2} \wedge x < \frac{9}{2}$$
         _____  
        /     \  
-------ο-------ο-------
       x2      x1
Solving inequality on a graph
Rapid solution [src]
And(-1/2 < x, x < 9/2)
$$- \frac{1}{2} < x \wedge x < \frac{9}{2}$$
(-1/2 < x)∧(x < 9/2)
Rapid solution 2 [src]
(-1/2, 9/2)
$$x\ in\ \left(- \frac{1}{2}, \frac{9}{2}\right)$$
x in Interval.open(-1/2, 9/2)