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Use the quadratic formula to solve the equation x^2-2x+5=0

Use the quadratic formula to solve the equation x^2-2x+5=0-example-1

1 Answer

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For the given equation, the solutions are
x = 1 \pm 2i.

Explanation:

Step 1:

For an equation of the form
ax^(2) +bx+c=0 the solution is
x=\frac{-b \pm \sqrt{b^(2)-4 a c}}{2 a}.

Here a is the coefficient of
x^(2), b is the coefficient of x and c is the constant term.

Comparing
x^(2) -2x+5=0 with
ax^(2) +bx+c=0, we get that a is 1, b is -2 and c is 5.

To get the solution, we substitute the values of a, b, and c in
x=\frac{-b \pm \sqrt{b^(2)-4 a c}}{2 a}.

Step 2:

Substituting the values, we get


x=\frac{-b \pm \sqrt{b^(2)-4 a c}}{2 a}=\frac{-(-2) \pm \sqrt{(-2)^(2)-4(1)(5)}}{2(1)}.


\frac{-(-2) \pm \sqrt{(-2)^(2)-4(1)(5)}}{2(1)} = (2 \pm √(4-20))/(2).


(2 \pm √(4-20))/(2) = (2 \pm √(-16))/(2).


(2 \pm √(-16))/(2) = (2)/(2) \pm (4(-1))/(2) = 1 \pm 2i.


x = 1 \pm 2i.

User Aleks G
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