Write the following statement by using appropriate grouping symbols:
The sum of $\mathrm{a}-\mathrm{b}$ and $3\mathrm{a}-2\mathrm{b}+5$ is subtracted from $4\mathrm{a}+2\mathrm{b}-7$.

Write the following statement by using appropriate grouping symbols:
Three times the sum of $2\mathrm{x}+\mathrm{y}-\left\{5-\left(\mathrm{x}-3\mathrm{y}\right)\right\}$ and $7\mathrm{x}-4\mathrm{y}+3$ is subtracted from $3\mathrm{x}-4\mathrm{y}+7$.

Write the following statement by using appropriate grouping symbols:
The subtraction of ${\mathrm{x}}^2-{\mathrm{y}}^2+4\mathrm{xy}$ from $2{\mathrm{x}}^2+{\mathrm{y}}^2-3\mathrm{xy}$ is added to $9{\mathrm{x}}^2-3{\mathrm{y}}^2-\mathrm{xy}$.

Simplify the following algebraic expression by removing grouping symbols.
$2\mathrm{x}+\left(5\mathrm{x}-3\mathrm{y}\right)$

Simplify the following algebraic expression by removing grouping symbols.
$3\mathrm{x}-\left(\mathrm{y}-2\mathrm{x}\right)$

Simplify the following algebraic expression by removing grouping symbols.
$5\mathrm{a}-\left(3\mathrm{b}-2\mathrm{a}+4\mathrm{c}\right)$

Simplify the following algebraic expression by removing grouping symbols.
$-2\left({\mathrm{x}}^2-{\mathrm{y}}^2+\mathrm{xy}\right)-3\left({\mathrm{x}}^2+{\mathrm{y}}^2-\mathrm{xy}\right)$

If  $3x+2y-\left\{x-\left(2y-3\right)\right\}$ can be expressed as $kx+ly-3$, then find the value of $k+l$.

Simplify the following algebraic expression by removing grouping symbols.
$5\mathrm{a}-\left\{3\mathrm{a}-\left(2-\mathrm{a}\right)+4\right\}$