Cara Isabella :
Não esqueça que (x+y)² = x² +2xy + y² ; ( x-y)² = x² - 2xy + y² ,ok?
Agora vamos por partes :
I)
(2a-6)² = (2a)² - 2.2a.6 + 6² = 4a² - 24 a + 36
II)
(- 2a+5)² =(-2a)² + 2.(-2a).5 + 5² =
= 4a² - 20a + 25
Então , I) - II) :
4a² - 24a + 36 - ( 4a² - 20a + 25 ) =
= 4a² - 24a + 36 - 4a² + 20a - 25 =
= - 4a + 11
Um abraço !!
2007-01-29 00:57:28
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answer #1
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answered by Carlos Homero Gonçalves Carrocin 6
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4a² - 24a+36-4a²+20a-25=0
cancela-se +4a²-4a²
-24a+20a= -4a
36-25=11
-4a+11=0
a=-11/-4
a=11/4
2007-01-28 14:41:13
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answer #2
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answered by Vera Lúcia 3
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Não sei dá -4a - 11 ou -4a + 11
hauhuahuahua
mas o que vale é a intenção né !
2007-01-28 14:26:13
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answer #3
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answered by Andrade 3
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(4a²+36) - (4a²+25)
4a²+36-4a²-25
=11
leva-se os nºs ao quadrado, depois elimiman-se os 4a² e diminui 25 do 36. OK?
2007-01-28 14:14:15
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answer #4
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answered by edwaldo r 3
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4a*2-24a+36 - [4a*2-20a+25] =
4a*2-24a+36 - 4a*2 + 20a - 25 =
= -4a+11
2007-01-28 14:11:09
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answer #5
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answered by Anonymous
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-4a+11
2007-01-28 13:55:48
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answer #6
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answered by ninjagaiden777 3
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-1
2007-01-28 13:46:36
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answer #7
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answered by Juma 6
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