a new home buyer pays 4 % annual interest on her first mortgage and 9 % annual interest on her second mortgage . if she borrowed a total of $ 300,000 , 80 % of which was in the first mortgage , what is her approximate monthly interest payment ?
"0.04 x + 0.09 y = 300000 [ 1 ] 0.04 x = 0.80 * 300000 = 240000 [ 2 ] 240000 + 0.09 y = 300000 - - > 0.09 y = 60000 [ 3 ] 240000 / 12 = 20000 [ 4 ] 60000 / 12 = 5000 [ 5 ] adding [ 4,5 ] we get : 25000 [ 6 ] dividing [ 6 ] / 2 to get an average we get 1.25 , ans a"
subtract(9, multiply(4, const_2))