1: \(=\dfrac{7xy^2\cdot3y}{7xy^2\cdot x}=\dfrac{3y}{x}\)
2: \(=\dfrac{2x^2\left(x+y\right)^2}{7xy\left(x+y\right)}=\dfrac{2x\left(x+y\right)}{7y}\)
3: \(=\dfrac{5\left(x+2\right)}{25x\left(x+2\right)}=\dfrac{1}{5x}\)
4: \(=\dfrac{\left(x+3\right)^2}{2\left(x+3\right)}=\dfrac{x+3}{2}\)