First, you would need to create an equation for this problem.

=

Next, you would cross multiply.
5x = 8,000
Now, all you would have to do is isolate the x. To do this, you would divide both sides by 5.
x = <span>
1,6001,600 people are considered middle class. I hope this helps!</span>
Answer:
X=(-1.5, 7.5)
Step-by-step explanation:
Simplifying
4x2 + -24x + -45 = 0
Reorder the terms:
-45 + -24x + 4x2 = 0
Solving
-45 + -24x + 4x2 = 0
Solving for variable 'x'.
Factor a trinomial.
(-3 + -2x)(15 + -2x) = 0
Set the factor '(-3 + -2x)' equal to zero and attempt to solve:
Simplifying
-3 + -2x = 0
Solving
-3 + -2x = 0
Move all terms containing x to the left, all other terms to the right.
Add '3' to each side of the equation.
-3 + 3 + -2x = 0 + 3
Combine like terms: -3 + 3 = 0
0 + -2x = 0 + 3
-2x = 0 + 3
Combine like terms: 0 + 3 = 3
-2x = 3
Divide each side by '-2'.
x = -1.5
Simplifying
x = -1.5
Set the factor '(15 + -2x)' equal to zero and attempt to solve:
Simplifying
15 + -2x = 0
Solving
15 + -2x = 0
Move all terms containing x to the left, all other terms to the right.
Add '-15' to each side of the equation.
15 + -15 + -2x = 0 + -15
Combine like terms: 15 + -15 = 0
0 + -2x = 0 + -15
-2x = 0 + -15
Combine like terms: 0 + -15 = -15
-2x = -15
Divide each side by '-2'.
x = 7.5
Simplifying
x = 7.5
Solution
x = {-1.5, 7.5}
This equation is not factor-able, so we can use the quadratic formula.
x=(-11+square root(11^2-4(-12*-3)))/(2*-12)
x=(-11+square root(-23))/(-24)
Since we have the square root of a negative in this equation, there are no real roots for the quadratic.
The explicit rule for the arithmetic sequence for the sequence is a(n) = 3n + 2.
<h3>What is a sequence?</h3>
It is defined as the systematic way of representing the data that follows a certain rule of arithmetic.
We have given:
and


The above expression represents the common ratio:
d = 3
First term:
a = 5
The explicit rule for the arithmetic sequence:
a(n) = 5 + (n - 1)3
a(n) = 3n + 2
Thus, the explicit rule for the arithmetic sequence for the sequence is a(n) = 3n + 2.
Learn more about the sequence here:
brainly.com/question/21961097
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