Question
Solve the following quadratic equation using formula method only
$x^2 - 7x - 5 = 0$
$x^2 - 7x - 5 = 0$
✓
Answer
$x^2-7 x-5=0 $
$a=1 ; b=-7 ; c=-5$
$ D=b^2-4 a c $
$=(-7)^2-4(1)(-5) $
$=49+20 $
$=69$
$ x=\frac{-b \pm \sqrt{b^2-4 a c}}{2 a}$
$ x=\frac{7 \pm \sqrt{69}}{2}$
$ x=\frac{7+\sqrt{69}}{2}, x=\frac{7-\sqrt{69}}{2}$
$a=1 ; b=-7 ; c=-5$
$ D=b^2-4 a c $
$=(-7)^2-4(1)(-5) $
$=49+20 $
$=69$
$ x=\frac{-b \pm \sqrt{b^2-4 a c}}{2 a}$
$ x=\frac{7 \pm \sqrt{69}}{2}$
$ x=\frac{7+\sqrt{69}}{2}, x=\frac{7-\sqrt{69}}{2}$
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