Question

como resolver os polimonios, conta armada pf

A- (7a-b)(7+b)

C- (3x-y) (2x+5y)

D- (5ax-4) (2ax-5)

E- (2r+s) (3r+2s)

Answer 1

A) (7a-b) . (7+b)

7a . 7 + 7ab - 7b - b . b

49a + 7ab - 7b - b²

C) (3x-y) . (2x+5y)

3x . 2x + 3x . 5y - 2xy - y . 5y

6x² + 13xy - 5y²

D) (5ax-4) . (2ax-5)

10a²x² - 25ax - 8ax + 20

10a²x² - 33ax + 20

E) (2r+s) . (3r+2s)

2r . 3r + 2r . 2s + 3rs + s . 2s

6r² + 4rs + 3rs + 2s²

6r² + 7rs + 2s²

Answer 2

Oi...

a)

(7a - b)(7 + b)

49a² + 7ab - 7b - b²

49a²  + 7ab - 7b - b²

c)

(3x - y)(2x + 5y)  

6x² + 15xy - 2xy - 5y²

6x² + 13xy - 5y²

d)

(5ax - 4)(2ax - 5)

10a²x² - 25ax - 8ax + 20

10a²x² - 33ax + 20

 

e)

(2r + s)(3r + 2s)

6r² + 4rs + 3rs + 2s²

6r² + 7rs + 2s²

Boas lições.