Question

Решите пожалуйстааа,дам 30 баллов

Answer 1

a)  (c-5)(c+2)=c^2+2c-5c-10=c^2-3c-10
б)  (6d+1)(d-3)=6d^2-18d+d-3=6d^2-17d-3
в)  (4m-n)(m+5n)=4m^2+20mn-nm-5n^2=4m^2+19mn-5n^2
г)   (y+3)(y^2-3y-4)=y^3-3y^2-4y+3y^2-9y-12=y^3-13y-12

Answer 2

2.a) а(2n-1)+3(2n-1)=(a+3)(2n-1)
1.a) (c-5)(c+2)=
$= {c}^{2} + 2c - 5c - 10$
$= {c}^{2} - 3c - 10$
б) (6d+1)(d-3)=
$= {6d}^{2} - 18d + d - 3 = {6d}^{2} - 17d - 3$
в) (4m-n)(m+5n)=
${4m}^{2} + 20mn - mn - {5n}^{2} = {4m}^{2} + 19mn - {5n}^{2}$
г) (y+3)(y^2-3y-4)=
${y}^{3} - {3y}^{2} - 4y + {3y}^{2} - 9y - 12 = {y}^{3} - 13y - 12$

3.(x-2)(x-5)-(x-3)(x+6)=8
${x}^{2} - 5x - 2x + 10 - ( {x}^{2} + 6x - 3x - 18) = 8$
${x}^{2} - 5x - 2x + 10 - ( {x}^{2} + 3x - 18) = 8$
${x}^{2} - 5x - 2x + 10 - {x}^{2} - 3x + 18 = 8$
-10x+28=8
-10x=8-28
-10x=-20
x=2
Вроде так,вообщем сколько смогла уж:)