2x + 13 = 19 or -(2x + 13) = 19
2x = 19 - 13 or -2x - 13 = 19
2x = 6 or -2x = 19 + 13
x = 6/2 or -2x = 32
x = 3 or x = 32/-2
or x = -16
|2x+13|=19
\(\begin{array}{|rcll|} \hline |2x+13| &=& 19 \quad & | \quad \text{square both sides} \\ (2x+13)^2 &=& 19^2 \\ 4x^2+52x + 13^2 &=& 19^2 \\ 4x^2+52x + 13^2 -19^2 &=& 0 \\ 4x^2+52x -192 &=& 0 \quad & | \quad : 4 \\ x^2+13x -48 &=& 0 \\ \hline \end{array} \)
\(\begin{array}{|rcll|} \hline ax^2+bx+c &=& 0 \\ x &=& \frac{-b \pm \sqrt{b^2-4ac}} {2a} \\\\ x^2+13x -48 &=& 0 \quad & | \quad a=1 \quad b=13 \quad c=-48 \\ x &=& \frac{-13 \pm \sqrt{13^2-4\cdot(-48)}} {2} \\ x &=& \frac{-13 \pm \sqrt{169+192}} {2} \\ x &=& \frac{-13 \pm \sqrt{361}} {2} \\ x &=& \frac{-13 \pm 19 } {2} \\\\ x_1 &=& \frac{-13 + 19 } {2} \\ x_1 &=& \frac{6} {2} \\ \mathbf{x_1} &\mathbf{=}& \mathbf{3} \\\\ x_2 &=& \frac{-13 - 19 } {2} \\ x_2 &=& \frac{-32 } {2} \\ \mathbf{x_2} &\mathbf{=}& \mathbf{-16} \\ \hline \end{array}\)