Question

1) Calcule as multiplicações.
a) 3. (x + y) =
b) 7. (x - 2y) =
c) 2x. (x + y) =
d) 4x. (a + b) =
e) 2x. (x2 - 2x + 5) =
f) (x + 5).(x + 2) =
g) (3x + 2).(2x + 1) =
h) (x + 7).(x - 4) =
i) (3x+4).(2x-1) =
j) (x-4y).(x-y)=

Alguém por favor​

Answer 1

Resposta:

b) 7(x-2y)= 7x-14y

c) 2x(x+y)= 2x²+2xy

d) 4x (a+b)= 4ax+4bx

e) 2x(x²-2x+5)= 2x³-4x²+10x

f) (x+5).(x+2)= x²+2x+5x+10= x²+7x+10

g) (3x+2).(2x+1)= 6x²+3x+4x+2= 6x²+7x+2

h) (x+7).(x-4)= x²-4x+7x-28= x²-3x-28

i) (3x+4).(2x-1)= 6x²-3x+8x-4= 6x²+5x-4

j) (x-4y).(x-y)= x²-xy-4xy+4y²= x²-5xy+4y²