Question

kendall says the sum of $(6x^{2} + 4xy + 2y^{2})$ and $(4x^{2} - 2xy - 3y^{2})$ is $(10x^{2} + 2xy - 5y^{2})$. what error did kendall make?
he combined the like terms $6x^{2}$ and $4x^{2}$ incorrectly.
he combined the like terms $4xy$ and $-2xy$ incorrectly.
he combined the like terms $2y^{2}$ and $-3y^{2}$ incorrectly.
he subtracted the polynomials instead of adding.

Explanation:

Step1: Combine $x^2$ terms

$6x^2 + 4x^2 = 10x^2$

Step2: Combine $xy$ terms

$4xy + (-2xy) = 2xy$

Step3: Combine $y^2$ terms

$2y^2 + (-3y^2) = -y^2$

Step4: Identify Kendall's error

Kendall calculated $2y^2 + (-3y^2)$ as $-5y^2$, which is wrong.

Answer:

C. He combined the like terms $2y^2$ and $-3y^2$ incorrectly.