Answer:
x³ - 5x² + 81x - 405 = 0
Step-by-step explanation:
Complex roots occur in conjugate pairs.
Thus given x = - 9i is a root then x = 9i is also a root
The factors are then (x - 5), (x - 9i) and (x + 9i)
The polynomial is the the product of the roots, that is
f(x) = (x - 5)(x - 9i)(x + 9i) ← expand the complex factors
= (x - 5)(x² - 81i²) → note i² = - 1
= (x - 5)(x² + 81) ← distribute
= x³ + 81x - 5x² - 405, thus
x³ - 5x² + 81x - 405 = 0 ← is the polynomial equation
Answer:
A
Step-by-step explanation:
the standard form of a quadratic equation is
ax² + bx + c = 0 : a ≠ 0
obtain (5 + x)(5 - x) = 7 in this form by expanding the factors
25 - x ² = 7 ( subtract 7 from both sides )
18 - x² = 0 ( multiply through by - 1 )
x² - 18 = 0 ← in standard form
with a = 1, b= 0 and c = - 18 → A
The term describes the elements that sets have
The Least amount of money we need is 130
She already has 45
She needs "e" more
Therefore:
45 + e ≥ 130
90 degrees. Looking at a clock, 12 o'clock going all the way around and back is a 360 degree spin. So 12, 3, 6, and 9 are all 1/4 of a 360 degree spin. If you divide 360 by, you would get a 90 degree turn for each of those numbers mentioned above.
