Question

(x+2y) square=x square+?+4y square

Anyone who brilliant please solve this question if you are brilliant so solve this question

Answer 1

Let the '?' be 'a'

( x + 2y ) ^{2} = x^{2} + a + 4y^{2}

x^{2} + ( 2 × x × 2y ) + (2y)^{2} = x^{2} + a + 4y^{2}

x^{2} + 4xy + 4y^{2} = x^{2} + a + 4y^{2}

x^{2} + 4xy + 4y^{2} - x^{2} + 4y^{2} = a

4xy = a