Question

wykonaj podane dzialania .bardzo prosze o szybka odpowiedz potrzebne na jutro.

(7x-2y)(-3x+9y-8)

2(a+3)(a-b)+3(b-2)(a-b)

(2a-3b+1)(8a+b)+9(a-5)

6(2-y)(5x+y)+3(x+y)(x-8)

Answer 1

(7x-2y)(-3x+9y-8)=-21x²+63xy-56x+6xy-18y²+16y=-21x²-18y²+69xy-56x+16y

 

2(a+3)(a-b)+3(b-2)(a-b)=2(a²-ab+3a-3b)+3(ab-b²-2a+2b)=

=2a²-2ab+6a-6b+3ab-3b²-6a+6b=2a²-3b²+ab

 

(2a-3b+1)(8a+b)+9(a-5)=16a²+2ab-24ab-3b²+8a+b+9a-45=16a²-3b²-22ab+17a+b-45

 

6(2-y)(5x+y)+3(x+y)(x-8)=6(10x+2y-5xy-y²)+3(x²-8x+xy-8y)=

=60x+12y-30xy-6y²+3x²-24x+3xy-24y=3x²-6y²+36x-12y-27xy