Answer: -1 and -5.
- A -1 and -5
- B -2 and -4
- C 1 and 5
- D 2 and 4
Correct answer: A. -1 and -5
Explanation: x² + 6x + 9 = 4, (x+3)² = 4, x+3 = ±2, x = -1 or x = -5.
A complex number z = a+ib is plotted as a point (or vector from the origin) on the Argand plane, with the real part along the horizontal axis and the imaginary part along the vertical; its modulus |z| is the vector's length, and its argument θ is the angle from the positive real axis.
Concept context
Complex numbers in a+ib form, modulus, argument, polar form, cube roots of unity, and quadratic equations with complex roots
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