(x-h)^2=4P(y-k), vertex is (h,k)
P is distance from vertex to directix
remember to subtract P from the y value of the vertex (p-k) and that y value is the directix, y=p-k
nut
ok so one way is to just graph them on a graphing utility
remember if the graph opens up, then the directix is below that
or we can convert to 4P(y-k)=(x-h)^2 form where P is distance from directix
I will only convert the 1st one fully, you should be able to do the rest
1. y=-x^2+3x+8
multiply both sides by -1 since we don't like the x^2 term negative
-y=x^2-3x-8
add8 to both sides
-y+8=x^2-3x
take 1/2 of linear coeficient and square it and add to both sides
-3/2=-1.5
(-1.5)^2=2.25
-y+10.25=x^2-3x+2.25
factor perfect square
-y+10.25=(x-1.5)^2
force undistribute -1 in left side
(-1)(y-10.25)=something, we don't care anymore for now
factor out a 4 in -1
4(-1/4)(y-10.25)
k=10.25
p=-1/4=-0.25
directix=k-p=10.25-(-0.25)=10.5
directix is y=10.5
basically completee the square with x and find P by force factoring a 4 out
2. directix: y=-1.75
3. directix: y=1.5
4. directix: y=17.25
5. d: -37.5
6. d: 9.25
7. d=2.625
order them yourself
Answer:
Step-by-step explanation:
So the first step is to add like terms since you can simplify the numerator by adding the two values sine they have the same variable and degree.
Add like terms:
![[\frac{8x^9}{2x}]^5](https://tex.z-dn.net/?f=%5B%5Cfrac%7B8x%5E9%7D%7B2x%7D%5D%5E5)
Divide by 2x (divide coefficient by 2, subtract coefficient degrees)
![[4x^8]^5](https://tex.z-dn.net/?f=%5B4x%5E8%5D%5E5)
Multiply exponents and raise 4 to the power of 5
The reason you multiply exponents is because you can think about it like this:
(4 * x * x * x * x * x * x * x * x) (this has one 4 and 8 x's because x is raised to the power of 8. Now if you do that 5 times which is what the exponent is doing you're going to have 40 x's and 8 4's. So it's essentially
(4 * x * x * x * x * x * x * x * x) * (4 * x * x * x * x * x * x * x * x) * (4 * x * x * x * x * x * x * x * x) * (4 * x * x * x * x * x * x * x * x) * (4 * x * x * x * x * x * x * x * x). If you group like terms you'll get (4 * 4 * 4 * 4 * 4) * (x * x * x * x * x * x * x * x * x * x * x * x * x * x * x * x * x * x * x * x * x * x * x * x * x * x * x * x * x * x * x * x * x * x * x * x * x * x * x * x * x * x * x * x * x). Which simplifies to 4^5 * x ^ (8 * 5) which further simplifies to the answer 1024x^40
11. 0.03, 3/10,1 1/8,1 5/6,2
The number is less than 190,000 and greater than 180,000
5,000 more than the number has 187 thousands
2000 less than the number has 4 hundreds
180, 000 <n> 190, 000
180,000 + 2000 = n = 5000-187, 000
182,000 = n = 182, 000
Or,
180, 000 <n> 190,000
n + 5000= 187, 000 n – 2000 = 180, 000
n= 187, 000- 5000 n = 180, 000 + 2000
n= 182, 000 n= 182, 000
The answer’s c, y=5/2x+10
