AD is the median of Triangle ABC on base BC. If angleADC=90degree prove that Triangle ABC is isosceles.
In ΔADB and ΔADC
BD =CD (Median AD bisects BC)
∠ADB = ∠ADC = 900
AD = AD (Common side)
∴ΔADB ΔADC (Using SAS rule).
⇒AB = AC
Therefore, ΔABC is isosceles.