Answer:
y = - 4x + 16
Step-by-step explanation:
Assuming you require the equation of the line passing through the points.
The equation of a line in slope- intercept form is
y = mx + c ( m is the slope and c the y- intercept )
Calculate m using the slope formula
m = (y₂ - y₁ ) / (x₂ - x₁ )
with (x₁, y₁ ) = (3, 4) and (x₂, y₂ ) = (5, - 4)
m =
=
= - 4, thus
y = - 4x + c ← is the partial equation
To find c substitute either of the 2 points into the partial equation
Using (3, 4), then
4 = - 12 + c ⇒ c = 4 + 12 = 16
y = - 4x + 16 ← equation of line
Not sure why such an old question is showing up on my feed...
Anyway, let

and

. Then we want to find the exact value of

.
Use the angle difference identity:

and right away we find

. By the Pythagorean theorem, we also find

. (Actually, this could potentially be negative, but let's assume all angles are in the first quadrant for convenience.)
Meanwhile, if

, then (by Pythagorean theorem)

, so

. And from this,

.
So,
Answer:
A) 21
Step-by-step explanation:
Mean:
(23 + 18 + 24 + 15 + 25)/5
105/5
21
D because that is the mean