D because there are 10 gallons of gas remaining as you can see on the y axis and 10 gallons is being used for each 10 miles because 10 x 10 is 100 and the graph is counting up by 10
Answer:
When we have a rational function like:
![r(x) = \frac{x + 1}{x^2 + 3}](https://tex.z-dn.net/?f=r%28x%29%20%3D%20%5Cfrac%7Bx%20%2B%201%7D%7Bx%5E2%20%2B%203%7D)
The domain will be the set of all real numbers, such that the denominator is different than zero.
So the first step is to find the values of x such that the denominator (x^2 + 3) is equal to zero.
Then we need to solve:
x^2 + 3 = 0
x^2 = -3
x = √(-3)
This is the square root of a negative number, then this is a complex number.
This means that there is no real number such that x^2 + 3 is equal to zero, then if x can only be a real number, we will never have the denominator equal to zero, so the domain will be the set of all real numbers.
D: x ∈ R.
b) we want to find two different numbers x such that:
r(x) = 1/4
Then we need to solve:
![\frac{1}{4} = \frac{x + 1}{x^2 + 3}](https://tex.z-dn.net/?f=%5Cfrac%7B1%7D%7B4%7D%20%3D%20%5Cfrac%7Bx%20%2B%201%7D%7Bx%5E2%20%2B%203%7D)
We can multiply both sides by (x^2 + 3)
![\frac{1}{4}*(x^2 + 3) = \frac{x + 1}{x^2 + 3}*(x^2 + 3)](https://tex.z-dn.net/?f=%5Cfrac%7B1%7D%7B4%7D%2A%28x%5E2%20%2B%203%29%20%3D%20%5Cfrac%7Bx%20%2B%201%7D%7Bx%5E2%20%2B%203%7D%2A%28x%5E2%20%2B%203%29)
![\frac{x^2 + 3}{4} = x + 1](https://tex.z-dn.net/?f=%5Cfrac%7Bx%5E2%20%2B%203%7D%7B4%7D%20%3D%20x%20%2B%201)
Now we can multiply both sides by 4:
![\frac{x^2 + 3}{4}*4 = (x + 1)*4](https://tex.z-dn.net/?f=%5Cfrac%7Bx%5E2%20%2B%203%7D%7B4%7D%2A4%20%3D%20%28x%20%2B%201%29%2A4)
![x^2 + 3 = 4*x + 4](https://tex.z-dn.net/?f=x%5E2%20%2B%203%20%3D%204%2Ax%20%2B%204)
Now we only need to solve the quadratic equation:
x^2 + 3 - 4*x - 4 = 0
x^2 - 4*x - 1 = 0
We can use the Bhaskara's formula to solve this, remember that for an equation like:
a*x^2 + b*x + c = 0
the solutions are:
![x = \frac{-b +- \sqrt{b^2 - 4*a*c} }{2*a}](https://tex.z-dn.net/?f=x%20%3D%20%5Cfrac%7B-b%20%2B-%20%5Csqrt%7Bb%5E2%20-%204%2Aa%2Ac%7D%20%7D%7B2%2Aa%7D)
here we have:
a = 1
b = -4
c = -1
Then in this case the solutions are:
![x = \frac{-(-4) +- \sqrt{(-4)^2 - 4*1*(-1)} }{2*(1)} = \frac{4 +- 4.47}{2}](https://tex.z-dn.net/?f=x%20%3D%20%5Cfrac%7B-%28-4%29%20%2B-%20%5Csqrt%7B%28-4%29%5E2%20-%204%2A1%2A%28-1%29%7D%20%7D%7B2%2A%281%29%7D%20%3D%20%5Cfrac%7B4%20%2B-%204.47%7D%7B2%7D)
x = (4 + 4.47)/2 = 4.235
x = (4 - 4.47)/2 = -0.235
You can divide the total number of outcomes.
Answer: A
Step-by-step explanation:
L=Length W=Width
3W=2L+2
4L=2L+2W+12
2L=2W+12
Option A
Hope this helps!! :)
Please let me know if you have any question or need further explanation