The nucleus `""_(84)^(202)X` emits an alpha particle and forms the nucleus Y. Represent this change in the form of an equation.

Explanation

To represent the change when the nucleus \( _{84}^{202}X \) emits an alpha particle and forms the nucleus \( Y \), we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Initial Nucleus**: The initial nucleus is given as \( _{84}^{202}X \). Here, 84 is the atomic number (number of protons) and 202 is the mass number (total number of protons and neutrons).

2. **Identify the Alpha Particle**: An alpha particle is represented as \( _{2}^{4}He \) or simply \( \alpha \). It consists of 2 protons and 2 neutrons.

...