Show that the points (0, 7, 10), (-1, 6, 6) and (-4, 9, 6) are the vertices of an isosceles right-angled triangle.
Let A = (0, 7, 10), B = (-1, 6, 6) and C = (-4, 9, 6)
AB = √(0+1)2+(7−6)2+(10−6)2
=√(1)2+(1)2+(4)2
=√18 =3√2
AC=√(0+4)2+(7−9)2+(10−6)2
=√(4)2+(−2)2+(4)2
=√36 (AB)2+(BC)2=AC2
⇒∠ABC=90∘ and AB = BC
Hence, (0, 7, 10), (-1, 6, 6) and (-4, 9, 6) are the vertices of an
isosceles right - angled triangle.