Answer:
The equation of the sphere with center (-2, 3, 7) and radius 7 is
.
The intersection of the sphere with the yz-plane is
.
Step-by-step explanation:
We know that any sphere can be represented by the following equation:

Where:
,
,
- Coordinates of the center of the sphere, dimensionless.
- Radius of the sphere, dimensionless.
If
and
, we obtain this expression:

The intersection of the sphere with the yz-plane observe the following conditions:
,
, 
Hence, the expression above can be reduced into this:

For this case we have the following expression:

To find the product, we apply distributive property that states:

So:

ANswer:

Answer:
The best statement which explains the relationship between lines AB and CD is "They are parallel because their slopes are equal" ⇒ A
Step-by-step explanation:
- Parallel lines have equal slopes and different y-intercepts
- The rule of the slope of a line passes through points (x1, y1) and (x2, y2) is m =

In the given figure
∵ The blue line passes through points A and B
∵ A = (-4, -2) and B = (4, 4)
∴ x1 = -4 and y1 = -2
∴ x2 = 4 and y2 = 4
→ Substitute them in the rule of the slope
∵ m(AB) =
=
=
= 
∴ The slope of line AB is 
∵ The green line passes through points C and D
∵ C = (0, -3) and D = (4, 0)
∴ x1 = 0 and y1 = -3
∴ x2 = 4 and y2 = 0
→ Substitute them in the rule of the slope
∵ m(CD) =
=
= 
∴ The slope of line CD is 
∵ The slope of line AB = the slope of line CD
∵ Parallel lines have the same slope
∴ AB // CD
∴ AB and CD are parallel lines
The best statement which explains the relationship between lines AB and CD is "They are parallel because their slopes are equal"
Answer:
X+13=116
Step-by-step explanation: