Question

Answer 1

a.

\(\dfrac{x^2-16}{4x-x^2}=\dfrac{\left(x-4\right)\left(x+4\right)}{-x\left(x-4\right)}=\dfrac{x+4}{-x}=-\dfrac{x+4}{x}\)

b.

\(\dfrac{x^2+4x+3}{2x+6}=\dfrac{\left(x+1\right)\left(x+3\right)}{2\left(x+3\right)}=\dfrac{x+1}{2}\)

c.

\(\dfrac{15x\left(x+y\right)^3}{5y\left(x+y\right)^2}=\dfrac{3x\left(x+y\right)}{y}\)

d.

\(\dfrac{\left(x+y\right)^2-z^2}{x+y+z}=\dfrac{\left(x+y+z\right)\left(x+y-z\right)}{x+y+z}=x+y-z\)