In the following figure, ∠AXY=∠AYX.
If BXAX=CYAY, then triangle ABC is isosceles.
True
In the given figure,
∠AXY=∠AYX
and BXAX=CYAY
In ΔAXY
∠AXY=∠AYX (given)
∴AY=AX (Sides opposite to equal angles)
BXAX=CYAY
⇒AXBX=AYCY
∴XY||BC
∴∠B=∠AXY and ∠C=∠AYX
(Corresponding angles)
But ∠AXY=∠AYX is given
∴∠B=∠C
∴AC=AB (Side opposite to equal angles)
∴ΔABC is an isosceles triangle.