The answer is <span>y=-4x+12 because they just moved the 4x
</span>
Your answers would beX = -1/5
X = 2/3
First join the log4 on the left:
log4( x*(x-3) = log4(-7x+21)
Then x = -7, works: -7*(-10)=70 = -7*(-7)+21
x=-3, 18 = 42, does not work
x=3 0=0 works,
However, when one puts x = -7 in the *original* exression, log4(-7) or log4(-10) do not exist (you know why?). So x= -7 is extraneous.
Now x=3 gives log4(0) on the left and right, which does not exist.
So, C is the answer, both are extraneous. Seem to work but indeed don't work in the *original* equation
Since V = (4/3) * pi * R^3
If R is halved, V' will reduce by a ratio of (1/2)^3 = 1/8
So V' = (1/8)V
Two line with the same slope are parallel, if two parallel lines have a different y-intercept they will never cross each other.
(Any two lines with different slopes will always intersect at some point)