C=9y²- 3y +27 =
D3y²+y²=
C=9y²- 3y +27 = 3(3y2-y+9)
D=3y²+y²=4y2
voilà
C = 9y² - 3y + 27 = 3(y² - y + 9)
D = 3y² + y² = 4y²
