Solve the equation x^{2}-8x-21=0 using the qu | vedclass

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(D) Comparing the given equation $x^{2}-8x-21=0$ with the standard form $ax^{2}+bx+c=0$,we get $a=1, b=-8, c=-21$.The discriminant $D$ is given by $D

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$4+\sqrt{37}$ and $4-\sqrt{37}$

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(D) Comparing the given equation $x^{2}-8x-21=0$ with the standard form $ax^{2}+bx+c=0$,we get $a=1, b=-8, c=-21$.The discriminant $D$ is given by $D = b^{2}-4ac$.$D = (-8)^{2} - 4(1)(-21) = 64 + 84 = 148$.Since $D > 0$,the equation has two distinct real roots.The roots are given by the quadratic formula $x = \frac{-b \pm \sqrt{D}}{2a}$.$x = \frac{-(-8) \pm \sqrt{148}}{2(1)} = \frac{8 \pm \sqrt{4 	imes 37}}{2} = \frac{8 \pm 2\sqrt{37}}{2}$.Dividing by $2$,we get $x = 4 \pm \sqrt{37}$.Thus,the roots are $4+\sqrt{37}$ and $4-\sqrt{37}$.

Solve the equation $x^{2}-8x-21=0$ using the quadratic formula.

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