Question

1-25b^2 0.25m^2-0.01n^2 25x^2+10x+1 -0.25b^2+16a^4 -x^2-4y^2

Answer 1

1-25b^2 =(1-5b)(1+5b)

0.25m^2-0.01n^2=(0.5m-0.1n)(0.5m+0.1n)

25x^2+10x+1 = (5x+1)^2

-0.25b^2+16a^4=(4a^2-o.5b)(4a^2+0.5b)

-x^2-4y^2+4xy=-(x^2-4xy+4y^2)=-(x-2y)^2

(x+y)^2+9(x-y)^2-6(x^2-y^2)

=(x+y-3x+3y)^2

=(4y-2x)^2=4(2y-x)^2