Using the quadratic formula, we solve for
.

Taking square roots on both sides, we end up with

Compute the square roots of -171 + 140i.


By de Moivre's theorem,

and the other root is its negative, -5 - 14i. We use the fact that (140, 171, 221) is a Pythagorean triple to quickly find

as well as the fact that


(whose signs are positive because of the domain of
).
This leaves us with

Compute the square roots of 5 + 12i.


By de Moivre,

and its negative, -3 - 2i. We use similar reasoning as before:




Lastly, compute the roots of -2i.



as well as -1 + i.
So our simplified solutions to the quartic are

<span>2(1+4n)+10(n-7)=2n-n
distribute
2+8n+10n-70=2n-n
combine like terms
18n-68=n
move n to other side
17n=68
divide
n=4</span>
Answer:
the first number is 3.4 and the second number is 1
Step-by-step explanation:
The computation of the two numbers is shown below:
Let us assume the first number be x
And, the second number be y
Now the equations are
5x + 4y = 21
And,
5x + 9y = 16
Now subtract equation 2 from equation 1
-5y = -5
y = 1
And, the x is
5x + 4 = 21
5x = 17
x = 3.4
Hence, the first number is 3.4 and the second number is 1
Well, since point A represents the center, and B represents a point on the outer line of the circle, segment AB would represent the radius, since the radius represents the length from the center to the outside of a circle
Hope this helps