Fiona is completing the square to solve the polynomial equation x2 - 4x + 1 = 0. What should be her first step?
Isolating the constant 1
Adding 4 to both sides of the equation
Isolating the second term, 4x
Adding 1 to both sides of the equation
Solution:
The given polynomial equation is
x2 - 4x + 1 = 0
Let us isolate 1
x2 - 4x = 1
We know that
2ab = -4x
2xb = -4x
b = -2
Let us take the square of b and add it to both sides
x2 - 4x + (-2)2 = 1 + (-2)2
x2 - 4x + 4 = 1 + 4
x2 - 4x + 4 = 5
(x - 2)2 = 5
Taking square root on both sides
√(x - 2)2 = √5
(x - 2) = ±√5
x = ±√5 + 2
Therefore, the first step should be isolating the constant 1.
Fiona is completing the square to solve the polynomial equation x2 - 4x + 1 = 0. What should be her first step?
Summary:
Fiona is completing the square to solve the polynomial equation x2 - 4x + 1 = 0. Her first step should be isolating the constant 1.
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