Question

Identify terms which contain $x$ and $y^2$ and give the coefficient of $x$ and $y^2$.
(i) $13y^2-8yx$
(ii) $2x^{2}y-15x{y}^2+7y^2$
[2 marks]

Answer 1

(i) $13y^2-8yx$

Here, $-8yx$ is the term containing 𝑥 and $13y^2$ is the term containing $y^2$. (0.5 mark)

The coefficient of $x$ is the product of the factors of $-8yx$ other than $x$.
Therefore, the coefficient of $x$ in $-8yx$ is $-8y$.
(0.5 mark)

The coefficient of $y^2$ is the product of the factors of $13y^2$ other than $y^2$.
Therefore, the coefficient of $y^2$ in $13y^2$ is 13. (0.5 mark)


(ii) $2x^{2}y-15x{y}^2+7y^2$

Here, $2x^{2}y$ and $-15x{y}^2$ are the terms containing $x$.
$-15x{y}^2$ and $7y^2$ are the terms containing $y^2$.
(0.5 mark)

The coefficient of 𝑥 in $2x^{2}y$ is $2xy$.
The coefficient of 𝑥 in $-15x{y}^2$ is $-15y^2$.

The coefficient of $y^2$ in $-15x{y}^2$ is $-15x$. (0.5 mark)
The coefficient of $y^2$ in $7y^2$ is 7. (0.5 mark)