Answer:
vertex =
(
4 , 25
)
Step-by-step explanation:
given a parabola in standard form y
= a
x
2
+
b
x
+
c
x
;
a
≠
0
then the x-coordinate of the vertex is
X vertex=-b/2a
y=-x2+8x+9 with a=-1 b=8 c=9
X vertex= -8/-2=4
substitute the value on the equation
Y vertex = -(4)squared+8(4)+9=25
Answer:
30 PS4 in the shipment are likely to be defective
Step-by-step explanation:
We take the estimate from the sample and estimate to all the PS4 in store. This means that we can solve this question using a rule of 3.
From the sample of 50 PS4, 3 are defective. How many are expected to be defective out of 500?
50PS4 - 3 defective
500 PS4 - x defective
![50x = 3*500](https://tex.z-dn.net/?f=50x%20%3D%203%2A500)
![x = \frac{1500}{50}](https://tex.z-dn.net/?f=x%20%3D%20%5Cfrac%7B1500%7D%7B50%7D)
![x = 30](https://tex.z-dn.net/?f=x%20%3D%2030)
30 PS4 in the shipment are likely to be defective
Answer:
The slant height is ![13m](https://tex.z-dn.net/?f=13m)
Step-by-step explanation:
The slant height of the cone,
, can be found using Pythagoras Theorem.
![l^2=12^2+(\frac{10}{2})^2](https://tex.z-dn.net/?f=l%5E2%3D12%5E2%2B%28%5Cfrac%7B10%7D%7B2%7D%29%5E2)
![l^2=12^2+(5)^2](https://tex.z-dn.net/?f=l%5E2%3D12%5E2%2B%285%29%5E2)
![l^2=144+25](https://tex.z-dn.net/?f=l%5E2%3D144%2B25)
![l^2=169](https://tex.z-dn.net/?f=l%5E2%3D169)
![l=\sqrt{169}](https://tex.z-dn.net/?f=l%3D%5Csqrt%7B169%7D)
![l=13m](https://tex.z-dn.net/?f=l%3D13m)