Verified Answer :

W0lf93

To solve x^2 + 20 = 2x.
First, we take all values to the left hand side and equate it to zero.
x^2 - 2x + 20 = 0
The quadratic formular is given by
x = (-b + or - sqrt(b^2 - 4ac)) / 2a, where: a = 1, b = -2 and c = 20
x = (-(-2) + or - sqrt((-2)^2 - (4 x 1 x 20))) / (2 x 1) = (2 + or - sqrt(4 - 80)) = (2 + or - sqrt(-76)) / 2 = (2 + or - 2sqrt(-19)) / 2 = 1 + or - sqrt(-19) = 1 + or - sqrt(19) i.
Therefore, the solution to x^2 + 20 = 2x is x = 1 + or - sqrt(19) i (option d).

Louli

Answer:

The last option is the correct one


Explanation:

The general form of the quadratic equation is:

ax² + bx + c = 0


The given equation is:

x² + 20 = 2x

which can be rewritten as:

x² - 2x + 20 = 0


By comparison:

a = 1

b = -2

c = 20


The quadratic formula used to get the roots is shown in the attached image


We now substitute to get the roots as follows:

x = \(\frac{2+\sqrt{(-2)^2-4(1)(20)}}{2(1)} = 1+\sqrt{19} i\)


or x = \(\frac{2-\sqrt{(-2)^2-4(1)(20)}}{2(1)} = 1-\sqrt{19} i\)


Hope this helps :)

View image Louli

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