2 years ago

Grace is 7 years older than Elena. Grace is also 15 years old.

Mathematics

1 answer:

Alex73 [517]2 years ago

4 0

The 3rd one is the answer

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Solve for x in the equation x squared minus 12 x + 59 = 0. x = negative 12 plus-or-minus StartRoot 85 EndRoot x = negative 6 plu

fgiga [73]

Value of x is: $x=6\pm\sqrt{23}i$

Option B is correct option.

Step-by-step explanation:

We need to solve the equation $x^2-12x+59=0$ and find value of x.

Using quadratic formula:

$x=\frac{-b\pm\sqrt{b^2-4ac}}{2a}$

Putting values of a, b and c and finding the value of x

a=1, b=-12 and c=59

$x=\frac{-b\pm\sqrt{b^2-4ac}}{2a}\\x=\frac{-(-12)\pm\sqrt{(-12)^2-4(1)(59)}}{2(1)}\\x=\frac{12\pm\sqrt{144-236}}{2}\\x=\frac{12\pm\sqrt{-92}}{2}\\x=\frac{12\pm\sqrt{92}i}{2}\\We\,\,know\,\sqrt{-1} \,\,is\,\,i\\x=\frac{12\pm2\sqrt{23}i}{2}\\x=\frac{2(6\pm\sqrt{23}i)}{2}\\x=6\pm\sqrt{23}i$