[tex]1)\\\\(x+4)^2=x^2+2*x*4+4^2=x^2+8x+16\\\\(2x+5)^2=(2x)^2+2*2x*5+5*2=4x^2+20x+25\\\\(3x+2y)=(3x)^2+2*3x*2y+(2y)^2=9x^2+12xy+4y^2[/tex]
[tex]2)\\\\(x-3 )^2=x^2-2*x*3+ 3^2=x^2-6x+9\\\\(3x-4)^2=(3x)^2-2*3x*4+4^2=9x^2-24x+16\\\\(2y-5x)^2=(2y)^2-2*2y*5x+(5x)^2=4y^2-20xy+25x^2[/tex]
[tex]3)\\\\(x-2 )(x+2)=x^2-2^2=x^2-4\\\\(5x+7 )(5x-7)=(5x)^2-7^2=25x^2-49\\\\(x-3y)(x+3y)=x^2-(3y)^2 =x^2-9y^2[/tex]
[tex]4)\\\\ (2+3)^2=5^2=25\\\\(5-7)^2=(-2)^2=4\\\\(3x+x)^2=(4x)^2=16x^2\\\\(5-4)(5+4) =1*9=9\\\\\\(a+b)^2=a^2+2ab+b^2\\\\(a-b)^2=a^2-2ab+b^2\\\\(a-b)(a+b)=a^2-b^2[/tex]
