Calculate the annual depreciation expense for a piece of machinery purchased by Oracle Corporation.

Item	Amount ($)
Cost of Machinery	500,000
Salvage Value	50,000
Useful Life	10 years
Depreciation Method	Straight-Line

Question:

Using the given data, calculate the annual depreciation expense for the machinery using the straight-line method. Show your calculations and explain the rationale behind using the straight-line method.