Addition and Subtraction of Algebraic Expressions

$\left(\frac{3n-2}{10}\right) - \left(\frac{n+3}{7}\right) + \left(\frac{4n-7}{3}\right)= n-1$

${\left(x^2+2x\right)}^2-3\left(x^2+2x\right)-y\left(x^2+2x\right)+3y$

The sum of $4x^{2}y \text{and} 8x^{3}y$ is:

Find $p\left(x\right)+q\left(x\right)$

$$\begin{gathered} p\left(x\right)=4x^2-3x+2x^3+5 \\ q\left(x\right)=x^2+2x+4 \end{gathered}$$

Find the sum of $xy-3, 5xy+8$ and $-2xy+1$

Add: $p\left(p-q\right), q\left(q-r\right) \mathrm{and} r\left(r-p\right)$.

Add: $x-5xy, 3xy-y, y-x$

Find the additive inverse of $-x^2+4$.

Find the additive inverse of $-3x+1$.

What is an additive inverse of $-4a^2+2a+3$?

What is an additive inverse of $2x^2+3x-5$?

What is an additive inverse of $2x+5$?

Sum of an expression and its additive inverse of an expression is equals to _____.

The additive inverse of an expression $\mathrm{ax}+\mathrm{b}$ is 

$\left(p^2+3m^2+2n^2\right)+\left(-2p^2+4m^2-5n^2\right)$ is :

Find the sum of $3{\mathrm{x}}^2\mathrm{y}+2{\mathrm{xy}}^2$ and$5{\mathrm{xy}}^2-8{\mathrm{x}}^2\mathrm{y}+3\mathrm{xy}$.

A rectangle has a length of ${\mathrm{x}}^2+4{\mathrm{y}}^{3 }$and a breadth of $-2{\mathrm{x}}^2+{\mathrm{y}}^3$. What is its perimeter ?

A Triangle has sides $\mathrm{x}+1, 3\mathrm{x}+6\mathrm{y}+2 \mathrm{and} \mathrm{x}-\mathrm{y}-9.$ Find its perimeter.

How much less is $7{\mathrm{a}}^2+9{\mathrm{b}}^2-21\mathrm{ab} \mathrm{than} {\mathrm{a}}^2-{\mathrm{b}}^2+2\mathrm{ab}$?

Subtract${\mathrm{a}}^2+3{\mathrm{b}}^2 \mathrm{from} -5{\mathrm{b}}^2+8{\mathrm{c}}^2$.