Solve D^2-DA+A-1=0

$$D ^ { 2 } - D A + A - 1 = 0$$

Solve for A (complex solution)

$$\left\{\begin{matrix}\\A=D+1\text{, }&\text{unconditionally}\\A\in \mathrm{C}\text{, }&D=1\end{matrix}\right.$$

Steps for Solving Linear Equation

Subtract D^{2} from both sides. Anything subtracted from zero gives its negation.

$$-DA+A-1=-D^{2}$$

Add 1 to both sides.

$$-DA+A=-D^{2}+1$$

Combine all terms containing A.

$$\left(-D+1\right)A=-D^{2}+1$$

The equation is in standard form.

$$\left(1-D\right)A=1-D^{2}$$

Divide both sides by -D+1.

$$\frac{\left(1-D\right)A}{1-D}=\frac{1-D^{2}}{1-D}$$

Dividing by -D+1 undoes the multiplication by -D+1.

$$A=\frac{1-D^{2}}{1-D}$$

Divide -D^{2}+1 by -D+1.

$$A=D+1$$

Solve for A

$$\left\{\begin{matrix}\\A=D+1\text{, }&\text{unconditionally}\\A\in \mathrm{R}\text{, }&D=1\end{matrix}\right.$$

Steps for Solving Linear Equation

Subtract D^{2} from both sides. Anything subtracted from zero gives its negation.

$$-DA+A-1=-D^{2}$$

Add 1 to both sides.

$$-DA+A=-D^{2}+1$$

Combine all terms containing A.

$$\left(-D+1\right)A=-D^{2}+1$$

The equation is in standard form.

$$\left(1-D\right)A=1-D^{2}$$

Divide both sides by -D+1.

$$\frac{\left(1-D\right)A}{1-D}=\frac{1-D^{2}}{1-D}$$

Dividing by -D+1 undoes the multiplication by -D+1.

$$A=\frac{1-D^{2}}{1-D}$$

Divide -D^{2}+1 by -D+1.

$$A=D+1$$

Solve for D

$$D=A-1$$

$$D=1$$