Answer:
Step-by-step explanation:
Like your other question, let's break it down systematically
6x + 9y - 9(6x - 3y + 8z)
Use the distributive property
6x + 9y - <u>9(6x - 3y + 8z)</u>
6x + 9y - 54x - 27y + 72z
Match like terms
6x - 54x = -48x
9y - 27y = -18y
72z - 48x - 18y
The standard deviation is the square root of the variance
so if the variance is 256, then the standard deviation is : sqrt 256 = 16 <==
a+b+c=0
[(a+b+c)^2=a^2+b^2+c^2+2ab+2ac+2bc]
[a^2+b^2+c^2+2ab+2ac+2bc=0]
[a^2+b^2+c^2=-(2ab+2ac+2bc)]
[a^2+b^2+c^2=-2(ab+ac+bc)] (i)
also
[a=-b-c]
[a^2=-ab-ac] (ii)
[-c=a+b]
[-bc=ab+b^2] (iii)
adding (ii) and (iii) ,we have
[a^2-bc=b^2-ac] (iv)
devide (i) by (iv)
[(a^2+b^2+c^2)/(a^2-bc)=(-2(ab+bc+ca))/(b^2-ac)]
the first 4 sets of coordinates are (2,1) (3,5) (4,9) and (5,13)