Is the number ​𝜋·–9 rational or irrational?

Answer 1

To determine whether $\pi \cdot -9$ is rational or irrational, we need to consider the properties of the numbers involved.

The number $\pi$ (pi) is known to be an irrational number, which means it cannot be expressed as a fraction of two integers. When we multiply an irrational number by a non-zero rational number (in this case, $-9$, which is a rational number), the result is still irrational.

Thus, $\pi \cdot -9$ is also an irrational number.

So, the answer is that $\pi \cdot -9$ is irrational.