Answer:
(x + 4)^2 + (y - 8)^2 = 81
or
(x + 4)^2 + (y - 8)^2 = 9^2 depending on how your teacher wants it written.
Step-by-step explanation:
The standard form for a circle is
(x + h)^2 + (y + k)^2 = r^2
r is the radius.
You are given the diameter
r = d/2
r = 18/2
r = 9
So you already have the right hand side of the equation
(x + h)^2 + (y + k)^2 = 9*2
(x + h)^2 + (y + k)^2 = 81
You basically have h and k as well. They come from the center point.
h = 4
k = - 8
So the equation of the circle (and the answer) is
(x + 4)^2 + (y - 8)^2 = 81
One question remains. Why do the x and y values change signs? If you know what the distance formula is, then what you are finding is the distance r of all points on the circle from the center of the circle.
It is the distance formula that is actually the formula for the circle.
Answer:
V = 24 m³
Step-by-step explanation:
The given question says that, 'Calculate the volume in cubic meters of a pool that is 8 m long, 2 m wide and 1.5 m deep'.
A pool is in the shape of a cubiod. The volume of the cuboid is given by :
V = lbh
Where
l is length, b is width and h is height
Put all the values,
V = 8 × 2 × 1.5
= 24 m³
So, the volume of the pool is equal to 24 m³.
Answer:
D. 21 m
Step-by-step explanation:
I calculated it logically
Look for what 'y' is when t = 1 and t = 2. Go to the graph, look at 1 on the bottom axis and go up till you find the point, then go all the way to the left to see what the y-value is, in this case it should be 1200. If you do the same with t = 2, you will get 2400. So our two ordered pairs are:
(1, 1200), (2, 2400)
We can find the slope of these two points by plugging them into the slope formula:

For points in the form of (x1, y1), (x2, y2). Plug in what we know:

Subtract:

Divide:

This is the slope, so we can write the equation: