Question
Solve each of the following equations using the formula:
$x^2+2 x-6=0$
$x^2+2 x-6=0$
✓
Answer
x^2 + 2x – 6 = 0
Here a = 1, b = 2 and c = − 6
Then $x =\frac{-b \pm \sqrt{b}^2-4 a c}{2 a}$
$=-\frac{(2) \pm \sqrt{(2)^2-4(1)(-6)}}{2(1)}$
$=\frac{-2 \pm \sqrt{28}}{2}$
$=\frac{-2 \pm 2 \sqrt{7}}{2}=-1 \pm \sqrt{7}$
Here a = 1, b = 2 and c = − 6
Then $x =\frac{-b \pm \sqrt{b}^2-4 a c}{2 a}$
$=-\frac{(2) \pm \sqrt{(2)^2-4(1)(-6)}}{2(1)}$
$=\frac{-2 \pm \sqrt{28}}{2}$
$=\frac{-2 \pm 2 \sqrt{7}}{2}=-1 \pm \sqrt{7}$
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