[" 45."ax-by=a^(2)+b^(2)],[x+y=2a]

x+y=a+b,ax-by=a^(2)-b^(2)

{:(x + y = a + b),(ax - by = a^(2) - b^(2)):}

The value of |{:(x^(2)+y^(2),ax+by,x+y),(ax+by,a^(2)+b^(2),a+b),(x+y,a+b,2):}| depends on

The value of |{:(x^(2)+y^(2),ax+by,x+y),(ax+by,a^(2)+b^(2),a+b),(x+y,a+b,2):}| depends on

The value of |{:(x^(2)+y^(2),ax+by,x+y),(ax+by,a^(2)+b^(2),a+b),(x+y,a+b,2):}| depends on

The value of |{:(x^(2)+y^(2),ax+by,x+y),(ax+by,a^(2)+b^(2),a+b),(x+y,a+b,2):}| depends on

The value of |(x^(2)+y^(2),ax+by,x+y),(ax+by,a^(2)+b^(2),a+b),(x+y,a+b,2)| depends on a)a b)b c)x d)None of these

If a circle passes through the point (a, b) and cuts the circle x^2 + y^2 = 4 orthogonally, then the locus of its centre is (a) 2ax+2by-(a^(2)+b^(2)+4)=0 (b) 2ax+2by-(a^(2)-b^(2)+k^(2))=0 (c) x^(2)+y^(2)-3ax-4by+(a^(2)+b^(2)-k^(2))=0 (d) x^(2)+y^(2)-2ax-3by+(a^(2)-b^(2)-k^(2))=0

The locus of the midpoints of the chords of the circle x^(2)+y^(2)-ax-by=0 which subtend a right angle at ((a)/(2),(b)/(2)) is ax+by=0ax+by=a^(2)=b^(2)x^(2)+y^(2)-ax-by+(a^(2)+b^(2))/(8)=0x^(2)+y^(2)-ax-by-(a^(2)+b^(2))/(8)=0