ABCD is a rectangle in which diagonal BD bisects ∠B. Then, ABCD is a square.
True
ABCD is a rectangle .... (given)
BD bisects ∠B ...(given)
Therefore ∠ABD=∠DBC=45∘
∠DAB=90∘
Therefore ∠ADB=180∘−90∘−45∘
=45∘
Hence, AD=AB (△ADB is isosceles)
ABCD is a square (Adjacent sides of a rectangle are equal)