Question

Resolva as equaçoes usando os recursos da  fatoração:
a) X²-8X=0
b) X²+3X=0
c) 9X²=5X
d) 5X²=-10X

Me ajudeeeem por favor

Answer 1

$a) \\ x^{2} -8x = 0 \\ \\ x(x - 8) =0 \\ \\ x' = 0 \\ \\ x - 8 = 0 \\ \\ x'' = 8$

S= {0, 8}
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$b) x^{2} +3 = 0 \\ \\ x(x + 3) \\ \\ x' = 0 \\ \\ x'' = 0 \\ \\ x + 3 = 0 \\ \\ x'' = -3$

S = {0, -3}
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$c) \\ 9x^2 = 5x \\ \\ 9 x^{2} -5x = 0 \\ \\ x(9x - 5) \\ \\ x' = 0 \\ \\ 9x -5 = 0 \\ \\ 9x = 5 \\ \\ x'' = \frac{5}{9}$

S = {0, $\frac{5}{9}$}

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$d) 5x^2 = -10x \\ \\ 5 x^{2} +10x = 0 \\ \\ 5x(x + 2) = 0 \\ \\ 5x = 0 \\ \\ x' = \frac{0}{5} \\ \\ x' = 0 \\ \\ x + 2 = 0 \\ \\ x'' = -2$

S = {0, -2}