factoraization `25-4y^2+21 y`.

Factorise: y ^(2) - 21y + 90

Fractorise: (3x-4y)^(2) - 25z ^(2)

Factories: 4y ^(2) + 20y + 25

Factorise the y ^(2) + 4y - 21

The locus of the centre of all circles passing through (2, 4) and cutting x^2 + y^2 = 1 orthogonally is : (A) 4x+8y = 11 (B) 4x+8y=21 (C) 8x+4y=21 (D) 4x-8y=21

The locus of the centre of all circles passing through (2, 4) and cutting x^2 + y^2 = 1 orthogonally is : (A) 4x+8y = 11 (B) 4x+8y=21 (C) 8x+4y=21 (D) 4x-8y=21

Factorize: 4x^2+12 x y+9y^2 (ii) x^4-10 x^2y^2+25 y^4 a^4-2a^2b^2+b^4

Express in factors : 4y^2+25y+21

The point of contact of the line 3x-4y-25=0 with the circle x^(2)+y^2=25 is

The simultaneous equations -3x + 4y = 7, 9/2 x - 6y = -21/6 " have " ………