Because of two sides [tex]AC[/tex] and [tex]BC[/tex] are equal, the angles [tex]\angle A[/tex] and [tex]\angle B[/tex] are also equal. We know that sum of angles of the triangle is equal [tex]180^{\circ}[/tex]. Let [tex]x[/tex] represent [tex]\angle B[/tex]. So, to find [tex]\angle B[/tex] we need to solve the equation:
[tex]2x+50=180[/tex]
[tex]2x=180-50[/tex]
[tex]2x=130[/tex]
[tex]x=130/2=65[/tex]
The answer is: [tex]\angle B = 65^\circ[/tex]
