Find the sum of x−2x+3 and x+2x+3.
(a) From the sum of 3x − y + 11 and − y − 11, subtract 3x − y − 11.
(b) From the sum of 4 + 3x and 5 − 4x + 2x2, subtract the sum of 3x2 − 5x and − x2 + 2x + 5.