Question

Como faz essa contar x²+7x+12=0? por favor me ajudem

Answer 1

$x^{2} -7x+12=0\\\\ a=1;b=7;c=12\\\\\\ \Delta=b^2-4ac\to \Delta=(-7)^2-4*1*12\to \Delta=49-48\to \Delta=1\\\\ x' \neq x''\\\\ x= \frac{-b\pm \sqrt{\Delta} }{2a} \to x= \frac{-(-7)\pm \sqrt{1} }{2*1a} \to x= \frac{7\pm 1}{2} \to \\\\\\ x'= \frac{7+ 1}{2} \to x'= \frac{8}{2} \to x'=4\\\\\\ x''= \frac{7- 1}{2} \to x''= \frac{6}{2} \to x''=3\\\\\\\\ S=\left \{ 3;4 \left \}$

Answer 2

Fórmula de Bhaskara
x²-7x+12=0
Determina os coeficientes
a=1 b=-7 c=12
Determina o Delta(Δ)fórmula (Δ=b²-4.a.c)
Δ=b²-4.a.c
Δ=-7²-4.1.12
Δ=49-48
Δ=1
Determina as raízes da equação fórmula (x'=-b+√Δ/2.a)
x'=-b+√Δ/2.a
x'=-(-7)+√1/2.1
x'=+7+1/2
x'=8/2
x'=4

Fórmula (x''=-b-√Δ/2.a)
x''=-b-√Δ/2.a
x''=-(-7)-√1/2.1
x''=+7-1/2
x''=6/2
x''=3

Substitui o ''x'' pelas raízes
x²-7x+12=0
(4)²-7.(4)+12=0
16-28+12=0
-12+12=0
     0=0

x²-7x+12=0
(3)²-7.(3)+12=0
9-21+12=0
-12+12=0
    0=0