Answer :

use distributive property
a(b+c)=ab+ac
y(9+2y)=9 times y+2y times 9=9y+2y^2
the answer is 9y+2y^2
y (9 + 2y)

= y (9) + y (2y)

= 9y + 2y²

= 2y² + 9y