Find the roots of the quadratic function by completing the square: x^2 + 4x - 1 = 0
2 answers:
Answer:
x = - 2 ±
Step-by-step explanation:
Given
x² + 4x - 1 = 0 ( add 1 to both sides )
x² + 4x = 1
To complete the square
add (half the coefficient of the x- term )² to both sides
x² + 2(2)x + 2² = 1 + 2² ← complete the square on the left side
(x + 2)² = 5 ← take the square root of both sides
x + 2 = ± ← subtract 2 from both sides
x = - 2 ±
roots are x = - 2 - or x = - 2 +
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Answer:
1/4
Step-by-step explanation:
To find the roots of the expression, factor the expression by GCF.
The roots are the factors set equal to 0 and solved for x.
2x = 0
x=0
4x-1 = 0
x = 1/4
The sum is the addition of the two roots 0 + 1/4 = 1/4