Question

Q # 7 combine like terms please

Answer 1

We have this expression:

$(-3y^2-7y-9)-(4y^2+6y+9)$

So let's solve this problem step by step. We need to order this expression. The way we choose is to match equal variables with equal exponents. 

So combining like terms we have:

$(-3y^2-7y-9)-(4y^2+6y+9)$

Applying distributive property in the second parenthesis:

$-3y^2-7y-9-4y^2-6y-9$

Grouping terms:

$(-3y^2-4y^2)+(-7y-6y)+(-9-9)$

Finally, adding and subtracting algebraic expressions:

$\boxed{-7y^2-13y-18}$

D. That is the correct answer