(b+3)(b-3)=
(2c-1)(2c+1)=
(3-1/5a)(3+1/5a)=
(2-x)(2+x)=
(7p+3)(7p-3)=
(k-y)(k+y)=
(x+3y)(x-3y)=
(10a-b)(b+10a)=
(2a-b)(2a+b)=
(y+4)(y-4)=
(8x+4a)(8a-4a)=
9p²-4=
1-25x²=
ПОЛНЫЙ ОТВЕТ. 20 БАЛЛОВ.

(b+3)(b-3)=b²-9(2c-1)(2c+1)=4c²-1(3-1/5 a)(3+1/5 a)=9 - 1/25 a²=9-0.04a²(2-x)(2+x)=4-x²(7p+3)(7p-3)=49p² - 9(k-y)(k+y)=k² - y²(x+3y)(x-3y)=x²-9y²(10a-b)(b+10a)=10a - b²(2a-b)(2a+b)=4a² - b²(y+4)(y-4)=y² - 16(8x+4a)(8x-4a)=64x² - 16a²9p² - 4=(3p+2)(3p -2)1 - 25x²=(1-5x)(1+5x)