I'm completely drawing a blank on how to do this.

A woman has $500,000 invested into two real estate properties. One yields an annual return on 12% and the other returns 15% per year on her investment. Her total annual return from the two investments is $64,500. If X represents 12% investment and Y represents 15% investment...

a. write an equation that states that the sum of the investments is equal to $500,000

x+y=500,000

b. What is the annual return on the 12% investment?

c. What is the annual return on the 15% investment?

d. write an equation that states the sum of the annual returns is $64,000.

12x+15y=64,500

e. solve the problem simultaneously to find how much is invested in each property.