Question

Ajudaaaa (equação 2° grau)

1) x²-12x+36=0

2) x²+11x-12=0

3) 3x²-7x+2=0​

Answer 1

Resposta:

1) x² - 12x + 36 = 0

a = 1, b = 12, c = 36

Δ = $b^{2}$ - 4ac

Δ = $12^{2}$ - 4.1.36

Δ = 144 - 144

Δ = 0

-$\frac{-b +- \sqrt{Δ} }{2*a}$

$\frac{-12 +- \sqrt{0} }{2*1}$

x1 = $\frac{-12 - {0} }{2*1}$ = $\frac{-12}{2}$ = -6

x2 = $\frac{-12 + {0} }{2*1}$ = $\frac{-12}{2}$ = -6

2) x² + 11x - 12 = 0

a = 1, b = 11, c = - 12

Δ = $b^{2}$ - 4ac

Δ = $11^{2}$ - 4.1.(-12)

Δ = 121 + 48

Δ = 169

-$\frac{-b +- \sqrt{Δ} }{2*a}$

$\frac{-11 +- \sqrt{169} }{2*1}$

x1 = $\frac{-11 - {13} }{2*1}$ = $\frac{-24}{2}$ = -12

x2 = $\frac{-11 + {13} }{2*1}$ = $\frac{2}{2}$ = 2

3) 3x²- 7x + 2 = 0​

a = 3, b = -7, c = 2

Δ = $b^{2}$ - 4ac

Δ = $(-7)^{2}$ - 4.3.2

Δ = 49 - 24

Δ = 25

-$\frac{-b +- \sqrt{Δ} }{2*a}$

$\frac{-(-7) +- \sqrt{25} }{2*3}$

x1 = $\frac{7 - {5} }{2*3}$ = $\frac{2}{6}$ = $\frac{1}{3}$

x2 = $\frac{7 + {5} }{2*3}$ = $\frac{12}{6}$ = 2