Answer:
A linear function is a polynomial function in which the variable x has degree at most one: {displaystyle f (x)=ax+b}. Such a function is called linear because its graph, the set of all points {displaystyle (x,f (x))} in the Cartesian plane, is a line.
Step-by-step explanation:
not sure if you wanted to know what it was.. ಠ_ಠ
Answer: D.) Cultural knowledge
Step-by-step explanation:
Answer:

Step-by-step explanation:
Hello,
let's follow the advise and proceed with the substitution
first estimate y'(x) and y''(x) in function of y'(t), y''(t) and t

Now we can substitute in the equation
![x^2y''(x)+9xy'(x)-20y(x)=0\\ e^{2t}[ \ e^{-2t}(\dfrac{d^2y}{dt^2}-\dfrac{dy}{dt}) \ ] + 9e^t [ \ e^{-t}\dfrac{dy}{dt} \ ] -20y=0\\ \dfrac{d^2y}{dt^2}-\dfrac{dy}{dt}+ 9\dfrac{dy}{dt}-20y=0\\ \dfrac{d^2y}{dt^2}+ 8\dfrac{dy}{dt}-20y=0\\](https://tex.z-dn.net/?f=x%5E2y%27%27%28x%29%2B9xy%27%28x%29-20y%28x%29%3D0%5C%5C%3C%3D%3E%20e%5E%7B2t%7D%5B%20%5C%20e%5E%7B-2t%7D%28%5Cdfrac%7Bd%5E2y%7D%7Bdt%5E2%7D-%5Cdfrac%7Bdy%7D%7Bdt%7D%29%20%5C%20%5D%20%2B%209e%5Et%20%5B%20%5C%20e%5E%7B-t%7D%5Cdfrac%7Bdy%7D%7Bdt%7D%20%5C%20%5D%20-20y%3D0%5C%5C%3C%3D%3E%20%5Cdfrac%7Bd%5E2y%7D%7Bdt%5E2%7D-%5Cdfrac%7Bdy%7D%7Bdt%7D%2B%209%5Cdfrac%7Bdy%7D%7Bdt%7D-20y%3D0%5C%5C%3C%3D%3E%20%5Cdfrac%7Bd%5E2y%7D%7Bdt%5E2%7D%2B%208%5Cdfrac%7Bdy%7D%7Bdt%7D-20y%3D0%5C%5C)
so the new equation is

the auxiliary equation is

so the solutions of the new equation are

with a and b real
as


hope this helps
do not hesitate if you have any questions
Answer:
The answer is 25 cm.
Step-by-step explanation:
Set the ones digit to x. 2x+1=7, so 2x=6, so x=3.
x+1 is the tens digit, so the tens digit is 4 and the number is 43.