what is x if x + 2 y = 100 and y = 25 ?
"substitute y by 25 in x + 2 y = 100 x + 2 ( 25 ) = 100 x + 50 = 100 if we substitute x by 50 in x + 50 = 100 , we have 50 + 50 = 100 . hence x = 50 correct answer b"
subtract(100, multiply(2, 25))