Answer:
b
Step-by-step explanation:
you can use a calculator, or this way of thinking about it :
the sqrt of 49 is 7. so rt46 is too small, and rt51 may be too big. rt50 is closer to rt49 ( 7's square) than rt47. so it is rt50
Answer:
Step-by-step explanation:
............................
31-40. C. 12 students sold that many, therefore it's the most.
Answer: 190800
Step-by-step explanation:
10 • 10 = 100
Than when you multiply anything 100 you just add two 0s to the end.
100 • 1908 = 190800
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