The third is because the prove is x = fifteen and if a number is next to a letter, it means multiply, sorry I could only do one.
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
Where is the answer choice????
Answer:
A
Step-by-step explanation:
The equation of a line in slope- intercept form is
y = mx + c ( m is the slope and c the y- intercept )
Calculate m using the slope formula
m = (y₂ - y₁ ) / (x₂ - x₁ )
with (x₁, y₁ ) = (0, 3) and (x₂, y₂ ) = (1, 1)
m = 
= - 2
note the line crosses the y- axis at (0, 3) ⇒ c = 3
y = - 2x + 3 → A
-4x - 2.4
explanation: 1.3 - 3.7 = -2.4
then you leave the -4x by itself since it’s the only variable
