Answer:
x=7
Step-by-step explanation:
7=2x-7
-2x-7-7
-2x=-14
x=-14÷2
x=-7
Answer
(a) 
(b) 
Step-by-step explanation:
(a)
δ(t)
where δ(t) = unit impulse function
The Laplace transform of function f(t) is given as:

where a = ∞
=> 
where d(t) = δ(t)
=> 
Integrating, we have:
=> 
Inputting the boundary conditions t = a = ∞, t = 0:

(b) 
The Laplace transform of function f(t) is given as:



Integrating, we have:
![F(s) = [\frac{-e^{-(s + 1)t}} {s + 1} - \frac{4e^{-(s + 4)}}{s + 4} - \frac{(3(s + 1)t + 1)e^{-3(s + 1)t})}{9(s + 1)^2}] \left \{ {{a} \atop {0}} \right.](https://tex.z-dn.net/?f=F%28s%29%20%3D%20%5B%5Cfrac%7B-e%5E%7B-%28s%20%2B%201%29t%7D%7D%20%7Bs%20%2B%201%7D%20-%20%5Cfrac%7B4e%5E%7B-%28s%20%2B%204%29%7D%7D%7Bs%20%2B%204%7D%20-%20%5Cfrac%7B%283%28s%20%2B%201%29t%20%2B%201%29e%5E%7B-3%28s%20%2B%201%29t%7D%29%7D%7B9%28s%20%2B%201%29%5E2%7D%5D%20%5Cleft%20%5C%7B%20%7B%7Ba%7D%20%5Catop%20%7B0%7D%7D%20%5Cright.)
Inputting the boundary condition, t = a = ∞, t = 0:

<h3>
Answer: Choice E</h3>
======================================================
Explanation:
Think of 25 as 25/1 and 5 as 5/1
Choice E is really saying
which becomes
. Note the second fraction flips and we change to a multiplication sign.
------------
Or you could think of it like this:

to help see why the answer is E.
Answer:
5 + x + 5 + x + x
Step-by-step explanation:
We are given 4 expressions and we have to determine which expressions shows a sum of five terms.
We use the process of elimination:
5(x + 5)
=5x+25 (distributing 5)
This contains sum of only two terms, <u>eliminate</u>.
5x
It contains only 1 term, <u>eliminate</u>.
5 + x + 5 + x + x
It contains 5 terms 5,x,5,x and x, <u>KEEP</u>!
5.
Only contains 1 term, <u>eliminate</u>.
With this said, were left with:
5 + x + 5 + x + x
Which is the correct answer! :)
For this case we can propose a system of equations:
x: Let the variable that represents the number of small cookies
y: Let the variable that represents the number of large cookies
According to the statement we have:

We multiply the first equation by -2:

We have the following equivalent system:

We add the equations:

We look for the value of the variable "x":

Answer:
They sold 80 small cookies and 50 large cookies