To find out how long the loan was for, we need to use the simple interest formula:Interest=P×r×twhere:P: is the principal amount (P15,900),r: is the interest rate per period (9%, or 0.09 as a decimal),t: is the time in years,Interest is the total interest paid (P8,586).Rearranging the formula to solve for t:t=Interest________ P×r Now, let's plug in the values: 8,586__________15,900×0.09 Calculating this:t=8,586÷1,431t=6So, the loan was for 6 years.i hope this help..