jacob is now 12 years younger than michael . if 3 years from now michael will be twice as old as jacob , how old will jacob be in 4 years ?
"jacob = x years , mike = x + 12 years 3 years from now , 2 ( x + 3 ) = x + 15 2 x + 6 = x + 15 x = 9 x + 4 = 13 years answer e"
add(4, subtract(add(12, 3), multiply(const_2, 3)))