Question

apresente a raizes reais das equações do 2° grau a seguir:

$4x {}^{2} - 24x + 20 = 0$
​

Answer 1

Resposta:

x' = 1

x'' = 5

Explicação passo a passo:

$4x^{2} -24x+20=0\\\\\frac{4x^{2} -24x+20}{4} =\frac{0}{4} \\\\x^{2} -6x+5=0$

$Para\ ax^{2} +bx+c=0:$

$a=1\ ,\ b=-6\ ,\ c=5$

$Fo\´rmula\ de\ Bhaskara:$

$x=\frac{-b\pm\sqrt{b^{2} -4ac} }{2a}\\\\x=\frac{-(-6)\pm\sqrt{(-6)^{2} -4(1)(5)} }{2(1)}\\\\x=\frac{6\pm\sqrt{36 -20} }{2}\\\\x=\frac{6\pm\sqrt{16} }{2}\\\\x=\frac{6\pm\sqrt{4^{2} } }{2}\\\\x=\frac{6\pm4 }{2}\\\\x=3\pm 2$

$x'=3-2\\\\x'=1\\\\\\x''=3+2\\\\x''=5$