Answer: y = -3(x +
)² +
,
,
<u>Step-by-step explanation:</u>
First, you need to complete the square:
y = -3x² - 5x + 1
<u> -1 </u> <u> -1 </u>
y - 1 = -3x² - 5x
y - 1 = -3(x² + 
y - 1 + -3(
) = -3(x² +
+
)
↑ ↓ ↑
= 
y - 1 -
= -3(x +
)²
y -
-
= -3(x +
)²
y -
= -3(x +
)²
y = -3(x +
)² +
Now, it is in the form of y = a(x - h)² + k <em>where (h, k) is the vertex</em>
Vertex =
,
Answer:
The rate of decrease is: 
Step-by-step explanation:
Given

---- We used minus because the rate is decreasing
Required
Rate of decrease when: 
The volume of the cube is:

Differentiate

Make dV the subject

Divide both sides by dt

Given that:
and 



<em>Hence, the rate of decrease is: 43.2mm^3/min</em>
Answer:
Remember while answering, 1 kilometer = 1,000 meters
5,000 ⇒ 5
6,000 ⇒ 6
7,000 ⇒ 7
8,000 ⇒ 8
9,000 ⇒ 9
Step-by-step explanation:
1 kilometer is 1,000 meters because "kilo" means 1,000
Knowing this we can make an equation to figure this out
When we know x, or meters, we can do y = x/1,000
When we know y, or kilometers, we can do x = 1,000y