if 3 x + 4 y = 60 and 6 x - 4 y = 12 , what is the product of x and y ?
given 3 x + 4 y = 60 - - - eq 1 6 x - 4 y = 12 - - eq 2 sum both eqns we get 9 x = 72 = > x = 8 sum 6 x in eq 2 = > 48 - 4 y = 12 . = > y = 9 now xy = 8 * 9 = 72 option d is correct answer .
multiply(divide(add(60, 12), add(6, 3)), divide(subtract(multiply(6, divide(add(60, 12), add(6, 3))), 12), 4))