36y2>_81 inequation

Given the inequality:
$$36 y_{2} \geq 81$$
To solve this inequality, we must first solve the corresponding equation:
$$36 y_{2} = 81$$
Solve:
$$x_{1} = 2.25$$
$$x_{1} = 2.25$$
This roots
$$x_{1} = 2.25$$
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
$$x_{0} = x_{1} - \frac{1}{10}$$
=
$$- \frac{1}{10} + 2.25$$
=
$$2.15$$
substitute to the expression
$$36 y_{2} \geq 81$$
$$36 y_{2} \geq 81$$

36*y2 >= 81

Then
$$x \leq 2.25$$
no execute
the solution of our inequality is:
$$x \geq 2.25$$

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