Question

Помогите пожалуйста срочно решить ​

Answer 1

$\displaystyle \tt 4) \: (1-5y)^2=1^2-2\cdot1\cdot5y+(5y)^2=1-10y+25y^2\\5) \: 100x^2-25y^2=(10x)^2-(5y)^2=(10x-5y)(10x+5y)\\6) \: 64m^2-49n^2=(8m)^2-(7n)^2=(8m-7n)(8m+7n)\\7) \: 8x^3-27y^3=(2x)^3-(3y)^2=(2x-3y)(4x^2+6xy+9y^2)$