An actor invested some money at 9% simple interest, and $42,000 more than three times the amount at 12% per annum. What we are after is amounts of interest invested at 9% and at 12%. Let's call them x and y respectively.
x=42000 at 9% = $3,780.00 = $45,780.00
y=3x42000 at 12% = $15,120.00 = $141,120.00
x+y=$186,900.00