X^3+3x^2+5x+8/x+1 multiply the whole equation by x x^4+3x^3+5x^2+8+1x x^4+3x^3+5x^2+x+8 factor out by parts (x^2-0.641604x+1.33244)(x^2+3.6416x+6.00403)
18% of 420 is 75.6. Multiply that by 63 to get 4762.8. 420 multiplied by 63 equals 26460. 26460 plus 4762.8 is 31222.8. 31222.8 divided by 63 is 495.6. So the answer is $495.60 per year.
