Question

simplifique as expressões em seu caderno
a)(a-2)²-2(a+2)
b)(y+5)²-y(y+10)
c)(x-3)²+(x+3)²
d)(a-b)²-(a+b).(a-b)
e)mx-my+mx-my
sabendo que m+m=10 e x-y=2

Answer 1

$a) \\ \\ (a - 2)^2 - 2(a + 2) \\ \\ \\ a^2 - 4a + 4 - 2a - 4 \\ \\=> a^2 - 6a$

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$b) \\ (y+5)^2-y(y+10) \\ \\ y^2 + 10y + 25 - y^2 - 10y \\ \\=> 25$

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$c) \\ \\ (x-3)^2+(x+3)^2 \\ \\ x^2 - 6x + 9 - (x^2 + 6x + 9 ) \\ \\ x^2 - 6x + 9 - x^2 - 6x - 9 \\ \\ => -12x$

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$d) \\ \\ )(a-b)^2-(a+b).(a-b) \\ \\ a^2 - 2ab + b^2 - (a^2 - b^2) \\ \\=> 2b^2 - 2ab$

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$e) \\ \\ mx-my+mx-my \\ \\ \\ m(2x- 2y) \\ \\ => 2m (x - y)$