Question

Proszę pomózcie
A) (x+1)(x-2)+(x+2)(x-10)

B) (5k+n)(k-2n)-k(4k+n)
C) (4y+3)(y-2)-2y(4-2y)

D) (-3c-2)(c-1)-c(c-2)

Answer 1

A) (x+1)(x-2)+(x+2)(x-10)=x²-x-2+x²-8x-20=2x²-9x-22

B) (5k+n)(k-2n)-k(4k+n)=5k²+9kn-2n²-4k²-kn=k²+8kn-2n²
C) (4y+3)(y-2)-2y(4-2y)=4y²-5y-6-8y+4y²=8y²-13y-6

D) (-3c-2)(c-1)-c(c-2)=-3c²+c+2-c²+2c=-4c²+3c+2

 

Answer 2

(x+1)(x-2) +(X+2)(X-10)=X^2-X-2+x^2-8x-20=2x^2-9x-22

(5k+n)(k-2n)-k(4k+n)=5k^2-9nk-n^2-4k^2-kn=k^2-10nk-n^2

(4y+3)(y-2)-2y(4-2y)=4y^2-5y-6-8y-4y^2=-11y-6

(-3c-2)(c-1)-c(c-2)=-3c^2+3c+2-c^2+2c=2c^2+5c+2