Solve y=sqrt{x+4}

$$y= \sqrt{ x+4 }$$

Solve for x

$$x=y^{2}-4$$

$$y\geq 0$$

Steps for Solving Radical Equations

Swap sides so that all variable terms are on the left hand side.

$$\sqrt{x+4}=y$$

Square both sides of the equation.

$$x+4=y^{2}$$

Subtract 4 from both sides of the equation.

$$x+4-4=y^{2}-4$$

Subtracting 4 from itself leaves 0.

$$x=y^{2}-4$$

Solve for x (complex solution)

$$x=y^{2}-4$$

$$arg(y)<\pi \text{ or }y=0$$

Solve for y

$$y=\sqrt{x+4}$$

$$x\geq -4$$