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:
The 3rd option is correct.
Step-by-step explanation:
This is because of an exponent rule that goes:
(xy)^z = x^z(y^z)
The whole thing gets raised to the power. Therefore only the 3rd one works (ps. if you can mark as brainliest that would be amazing, but if not that's fine)
A = the number before x^2 = 3
b = the number before x = 5
To find the axis of symmetry: -b/2a
x = -5/6
Step-by-step explanation:
Given equation of circle is,

again the another form of circle is,

now equating the values of f in both equations,
-k=-3
i.e. k=3
therefore k=3
The amount of material/ number of pillows made
16/12 = 4/3 = 1 1/3
So the answer lies between integers 1 & 2