Respostas

2014-05-08T08:46:52-03:00
A)   x² - 12x + 36 = 0
2x - 12x = 0 - 36
-10x = -36 (-1)
10x = 36
x =  \frac{36}{10}
x = 3.6
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B)  x² - 20x + 75 = 0
2x - 20x = 0 - 75
-18x = -75 (-1)
18x = 75
x =  \frac{75}{18}
x = 4.1
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C)   x² - 14x + 48 = 0
2x - 14x = 0 - 48
- 12x = - 48 (-1) 
12x = 48
x =  \frac{48}{12}
x = 4
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D)  5x² - 80x + 16 = 0
25x - 80x = 0 - 16
- 55x = - 16 (-1)
x =  \frac{16}{55}
x = 0.2