$a^{2} + 5 a + 7 = 0$ then find values $a$ ?

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Solution

A] $a^{2} + 5 a + 7 = 0$
$a_{1} = 1$
$b_{1} = 5$
$c_{1} = 7$
using $x = \frac{- b_{1} + \sqrt{(b_{1})^{2} - 4 a_{1}, c_{1}}}{2 a_{1}}$
$a = \frac{- 5 + \sqrt{(5)^{2} - 4 \times 1 \times 7}}{2 \times 1}$
$= \frac{- 5}{+} \sqrt{25 - 28} 2 = \frac{- 3 \pm \sqrt{- 3}}{2}$
$∴ a = \frac{- 5 \pm \sqrt{3 i}}{2}$

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a2+5a+7=0 then find values a ?

A] a2+5a+7=0a1=1b1=5c1=7using x=−b1+√(b1)2−4a1,c12a1a=−5+√(5)2−4×1×72×1=−5+√25−282=−3±√−32∴a=−5±√3i2

$a^{2} + 5 a + 7 = 0$ then find values $a$ ?