Given the triangle XYZ with the following parameters
[tex]\begin{gathered} |XZ|=|YZ| \\ \measuredangle YXZ=40^0 \\ \measuredangle XZY=(13x-20)^0 \\ \text{Therefore} \\ \measuredangle ZYX=40^0 \end{gathered}[/tex]The diagram of the triangle is shown below
To find the value of x, we will apply sum of interior angle of triangle theorem
[tex]\begin{gathered} 40^0+40^0+(13x-20)^0=180^0(\text{ sum of angles in a triangle)} \\ 80^0+13x-20^0=180^0 \\ 13x+60^0=180^0 \\ 13x=180^0-60^0 \\ 13x=120^0 \\ x=\frac{120^0}{13} \\ x=9.2308^0 \end{gathered}[/tex]Hence, the value of x is 9.2308°
