Simplify brackets
2/5(x - 4) = 2x
Simplify 2/5(x - 4) to 2(x - 4)/5
2(x - 4)/5 = 2x
Multiply both sides by 5
2(x - 4) = 10x
Divide both sides by 2
x - 4 = 5x
Subtract x from both sides
-4 = 5x - x
Simplify 5x - x to 4x
-4 = 4x
Divide both sides by 4
-1 = x
Switch sides
<u>x = -1</u>
Complete Question
The complete question is shown on the first uploaded image
Answer:
The point of diminishing returns (x , y ) is (11, 21462)
Step-by-step explanation:
From the question we are told that
The function is 
Here R(x) represents revenue (in thousands of dollars) and x represents the amount spent on advertising (in thousands of dollars).
Now differentiating R(x) we have

Finding the second derivative of R(x)

at inflection point 
So 
=> 
substituting value of x into R(x)


Now the point of diminishing returns (x , y ) i.e (x , R(x) ) is
(11, 21462)
Answer:
nth term = 
Step-by-step explanation:
Let us assume that the given sequence is a G.P.
Now, if the first term of the G.P. is a and the common ratio is r, then
Third term =
.......... (1) and
20th term =
........... (2)
Now, dividing equation (2) with equation (1) we get
⇒
⇒ r = 1.2.
Hence, from equation (1) we get
a(1.2)² = 11
⇒ a = 7.639 (Approx.)
Therefore, the general term of the sequence i.e. nth term =
(Answer)
The answer is $14 because 65% of $40 is 26 and 40-26=14