Given the inequality:
$$- 25 x + 49 < 0$$
To solve this inequality, we must first solve the corresponding equation:
$$- 25 x + 49 = 0$$
Solve:
Given the linear equation:
49-25*x = 0
Move free summands (without x)
from left part to right part, we given:
$$- 25 x = -49$$
Divide both parts of the equation by -25
x = -49 / (-25)
$$x_{1} = \frac{49}{25}$$
$$x_{1} = \frac{49}{25}$$
This roots
$$x_{1} = \frac{49}{25}$$
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
$$x_{0} = x_{1} - \frac{1}{10}$$
=
$$- \frac{1}{10} + \frac{49}{25}$$
=
$$\frac{93}{50}$$
substitute to the expression
$$- 25 x + 49 < 0$$
$$- \frac{25 \cdot 93}{50} + 49 < 0$$
5/2 < 0
but
5/2 > 0
Then
$$x < \frac{49}{25}$$
no execute
the solution of our inequality is:
$$x > \frac{49}{25}$$
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