Mean the the total of all values, divided by the number of values
Answer:
The mean is 20
Step-by-step explanation:
17+19+21+23=80
80 div 4 = 20
Answer:

Step-by-step explanation:
A hyperbola is the locus of a point such that its distance from a point to two points (known as foci) is a positive constant.
The standard equation of a hyperbola centered at the origin with transverse on the x axis is given as:

The coordinates of the foci is at (±c, 0), where c² = a² + b²
Given that a hyperbola centered at the origin with x-intercepts +/- 4 and foci of +/-2√5. Since the x intercept is ±4, this means that at y = 0, x = 4. Substituting in the standard equation:
I don't feel like explaining so...
a. = 4
The foci c is at +/-2√5, using c² = a² + b²:
B = 2
Substituting the value of a and b to get the equation of the hyperbola:

60.
The question gives you the fact that 6 bricks is 2 feet high.
What do you do to get from 2 to 20?
You multiply by 10.
Since you multiplied one thing by 10, you must do it to the other side so it remains balanced.
2 ft x 10ft = 20ft
6 bricks x 10 bricks = 60 bricks
Answer:
1 pair of boots and 6 sweaters
Step-by-step explanation:
70+20s = 135
-70 -70
20s = 135
divide 20 both sides
s = 6.75
She can buy 6 sweaters because she cannot buy half a sweater.
s - sweaters
I need brainliest please