Answer: 
Step-by-step explanation:
Let the given parabolic mirror opens upwards and vertex=(0,0)
Focus point of the parabolic mirror is located 2 inches from the vertex of the mirror. ∴ p=2
Since, the parabola opens upward, then the equation of the parabola is of the form 
Substitute the value of p=2 in this, we get the equation of the parabolic mirror

Hence, the equation of the parabola that models the cross section of the mirror is 
The complete factorization of the equation 81x² - 100 is; (9x - 10)(9x + 10)
<h3>How to factorize quadratic equations?</h3>
We are given the quadratic equation;
81x² - 100
Now, according to quadratic identities, we know that;
(a + b) * (a - b) = a² - b²
Now, our equation can also be expressed as;
81x² - 100 = 9²x² - 10²
Thus, applying the quadratic identity gives us;
(9x + 10)(9x - 10)
Read more about factorization of quadratic equations at; brainly.com/question/1214333
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Line Q??? You don't really have an image of it
10/18 because 18-8=10 and the total amount is 18 so the fraction is 10/18
Answer:
The answer to your question is 10 in
Step-by-step explanation:
Data
Circumference = 20π in
Diameter = ?
Formula
Circumference = 2πr
Process
1.- Equal the formula to the value
2πr = 20π
2.- Solve for r
r = 20π/2π
3.- Simplification
r = 10/2
4.- Find the diameter
diameter = 2r
diameter = 2(10/2)
diameter = 10 in