man has $460,000 invested in three rental properties. One property earns 7.5% per year on the investment, the second earns 8%, and the third eams 9% The total annual earnings from the roperties is $38,650, and the amount invested at 9% equals the sum of the first two investments. Let x equal the investment at 7.5%, y equal the investment at 8%, and z represent the investme 9% Complete parts (a) through (d) below. a. Write an equation that represents the sum of the three investments Type an equation. Do not include the $ symbol in your appet