## Multiplying Imaginary Numbers: (4i)(5i)

In the realm of mathematics, imaginary numbers are a fascinating concept, denoted by the symbol **i**, where **i² = -1**. Let's delve into multiplying two imaginary numbers: **(4i)(5i)**.

### Understanding the Process

Multiplying imaginary numbers follows the same principles as multiplying any other algebraic expressions. The key difference lies in the fact that **i²** is always equal to **-1**.

**Multiply the coefficients:**4 x 5 = 20**Multiply the imaginary units:**i x i = i²**Substitute i² with -1:**20 x (-1) = -20

### The Result

Therefore, the product of (4i)(5i) is **-20**.

### Key Takeaways

- Imaginary numbers are a fundamental concept in mathematics.
- The product of two imaginary numbers can result in a real number.
- Understanding the relationship between
**i**and**-1**is crucial for calculations involving imaginary numbers.