Given that line AB is the angle bisector or

Equation is x-1=3x-11
x= 5

Explanation:
BC and BD are congruent. I forgot the name of the theorem but it involves proving the bisected angle’s triangles congruent.
So here’s my attempt at that:
Angle: Angle BAC and BAD are congruent as they are bisected.
Angle: The right angles are congruent.
Side: BA is congruent for both triangles. The triangles are congruent by AAS, so BC and BD must be congruent.
BC=BD
x-1=3x-11
10=2x
x=5

How many groups are there?