Y2-16 25x2-49 x2-8x+16 4a2+20ab+25b2

Question

Y2-16 25x2-49 x2-8x+16 4a2+20ab+25b2

Answer 1

Y²-16 = (y-4)(y+4).
25x²-49 = (5x-7)(5x+7).
x²-8x+16 = (x-4)².
4a²+20ab+25b² = (2a+5b)².