Solving Equations Using All Methods: Domain of definition

$\frac{25a+4b}{7y+4\cdot3+2}=9b$

What is the field of application of the equation?

$y\operatorname{\ne}-2$

$\frac{3x:4}{y+6}=6$

What is the field of application of the equation?

$y\operatorname{\ne}-6$

$\frac{6}{x+5}=1$

What is the field of application of the equation?

$x\operatorname{\ne}-5$

$\frac{x+y:3}{2x+6}=4$

What is the field of application of the equation?

$x\operatorname{\ne}-3$

$\frac{xyz}{2(3+y)+4}=8$

What is the field of application of the equation?

$y\ne-5$

$\frac{\sqrt{15}+34:z}{4y-12+8:2}=5$

What is the field of application of the equation?

$y\operatorname{\ne}2$