1. 1) х^2 + 6х+9
2) 4а^2 - 20аб + 25b^2
3) z^2 - 16
2. 1) (х-5)(х+5)
2) (6m-10n)(6m+10n)
3) 16 - 8y +y^2
4) (6a+2b)^2
3. 9m^2 - 42mn +49n^2 - 9m^2 - 45mn = -87mn +49n^2 = n(49n - 87m)
4. 1) x^2 = 64
x = ±8
2) х^2 + 10x + 25 - x^2 + 2x - 1 = 48
12x + 24 = 48
12x = 48 - 24
12x = 24
x = 24/12
х = 2
5. m^2 + 10m + 25 - m^2 + 16 = 10m +16
m= - 3.5 значит 10 * (-3.5) = -35