2 - 3i is just another of writing (2, -3) in the cartesian plane, the 2-3i however is using the "imaginary axis" for the imaginary plane, is all however the imaginary axis is simply the equivalent of the y-axis. Likewise 9+21i is just (9,21), so let's just use the distance formula.
![\bf ~~~~~~~~~~~~\textit{distance between 2 points} \\\\ (\stackrel{x_1}{2}~,~\stackrel{y_1}{-3})\qquad (\stackrel{x_2}{9}~,~\stackrel{y_2}{21})\qquad \qquad d = \sqrt{( x_2- x_1)^2 + ( y_2- y_1)^2} \\\\\\ d=\sqrt{[9-2]^2+[21-(-3)]^2}\implies d=\sqrt{(9-2)^2+(21+3)^2} \\\\\\ d=\sqrt{7^2+24^2}\implies d=\sqrt{49+576}\implies d=\sqrt{625}\implies d=25](https://tex.z-dn.net/?f=%5Cbf%20~~~~~~~~~~~~%5Ctextit%7Bdistance%20between%202%20points%7D%20%5C%5C%5C%5C%20%28%5Cstackrel%7Bx_1%7D%7B2%7D~%2C~%5Cstackrel%7By_1%7D%7B-3%7D%29%5Cqquad%20%28%5Cstackrel%7Bx_2%7D%7B9%7D~%2C~%5Cstackrel%7By_2%7D%7B21%7D%29%5Cqquad%20%5Cqquad%20d%20%3D%20%5Csqrt%7B%28%20x_2-%20x_1%29%5E2%20%2B%20%28%20y_2-%20y_1%29%5E2%7D%20%5C%5C%5C%5C%5C%5C%20d%3D%5Csqrt%7B%5B9-2%5D%5E2%2B%5B21-%28-3%29%5D%5E2%7D%5Cimplies%20d%3D%5Csqrt%7B%289-2%29%5E2%2B%2821%2B3%29%5E2%7D%20%5C%5C%5C%5C%5C%5C%20d%3D%5Csqrt%7B7%5E2%2B24%5E2%7D%5Cimplies%20d%3D%5Csqrt%7B49%2B576%7D%5Cimplies%20d%3D%5Csqrt%7B625%7D%5Cimplies%20d%3D25)
<span>The expression of the square root of 19x must be simplified when x is equal to 28. This is because possible factors of 28 can be seen to be 4 and 7, and 4 is a perfect square. This means it can be pulled outside of the square root when evaluated. The other options include only prime factors that could not be pulled out. (3,5), (3,7), (1,41)
28 simplifies as such:
Sqrt(19*28) = Sqrt(19*4*7) = 2*Sqrt(19*7) = 2*Sqrt(133).</span>
Answer:
The intermediate step are;
1) Separate the constants from the terms in x² and x
2) Divide the equation by the coefficient of x²
3) Add the constants that makes the expression in x² and x a perfect square and factorize the expression
Step-by-step explanation:
The function given in the question is 6·x² + 48·x + 207 = 15
The intermediate steps in the to express the given function in the form (x + a)² = b are found as follows;
6·x² + 48·x + 207 = 15
We get
1) Subtract 207 from both sides gives 6·x² + 48·x = 15 - 207 = -192
6·x² + 48·x = -192
2) Dividing by 6 x² + 8·x = -32
3) Add the constant that completes the square to both sides
x² + 8·x + 16 = -32 +16 = -16
x² + 8·x + 16 = -16
4) Factorize (x + 4)² = -16
5) Compare (x + 4)² = -16 which is in the form (x + a)² = b
is the boundary of the triangle 
, then by Green's theorem
