Question 759377
20% down payment, so 80% is financed


80% of $128,000 = 0.8*128000 = 102,400 is financed (ie loaned out)


Turn to the formula P = L[c(1 + c)^n]/[(1 + c)^n - 1]


P = monthly payment
L = amount loaned out
c = monthly interest rate
n = number of payments


In this case


P = unknown
L = 102400
c = 0.095/12 = 0.00791666666666667
n = 30*12 = 360


Plug all that into the formula to get 


P = L[c(1 + c)^n]/[(1 + c)^n - 1]


P = 102400[0.00791666666666667(1 + 0.00791666666666667)^360]/[(1 + 0.00791666666666667)^360 - 1]


P = 861.03470815104


P = 861.03


The monthly payment is <font color="red">$861.03</font>