allerySolve by completing the square: x^2 + 6x + 5 = 0. Roots are
A-1 and 5
B1 and 5
C-1 and -5
D1 and -5
Answer & Solution
Correct answer: C. -1 and -5
1. Rewrite: x^2 + 6x = -5, add 9 on both sides.
2. (x + 3)^2 = 4.
3. Take square root: x + 3 = plus or minus 2.
4. So x = -1 or x = -5.
_Source: Selina Concise Mathematics Class 10, Ch 5 Quadratic Equations (Mistral OCR'd PDF), section on completing the square_
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