Question

delta me ajudem por favor
${ \times }^{2} - 4 \times + 9 = 0$

$2 { \times }^{2} - 8 \times + 8 = 0$
$\times { }^{2} - 7 \times + 12 = 0$
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Answer 1

Explicação passo-a-passo:

$x {}^{2} - 4x + 9 = 0 \\ \beta = b { }^{2} - 4ac \\ \beta = ( - 4) {}^{2} - 4 \times 1 \times 9 \\ \beta = 16 - 36 \\ \beta = - 20$

$2x {}^{2} - 8x + 8 = 0 \ \\ \\ x {}^{2} - 4x + 4 = 0 \\ \beta = b { }^{2} - 4ac \\ \beta = ( - 4) {}^{2} - 4 \times 1 \times 4 \\ \beta = 16 - 16 \\ \beta = 0$

$x {}^{2} - 7x + 12= 0 \ \\ \beta = b { }^{2} - 4ac \\ \beta = ( - 7) {}^{2} - 4 \times 1 \times 12\\ \beta = 49 - 48 \\ \beta = 1$