The straight lines mean absolute value
so x = -16 and x = 16
C=πr²
c=22/7*28²
c=22/7*784
c=(22*784)/7
c=22*112=2464
Answer:
45x^3 + 123x^2 + 104x + 28
=(45x^3 + 60x^2 + 20x) + (63x^2 + 84x + 28)
=5x(9x^2 + 12x + 4) + 7(9x^2 + 12x + 4)
=(5x + 7)(9x^2 + 12x + 4)
=(5x + 7)(3x + 2)^2
=> Option D is correct
Hope this helps!
:)
It's difficult to make out, but I think the task is to expand

Write the number in polar form first:

By DeMoivre's theorem, you have

and converting back to Cartesian form, this number is equivalent to
Answer:the last one I’m not really sure