To solve this we are going to use the half life equation

Where:

is the initial sample

is the time in years

is the half life of the substance

is the remainder quantity after

years
From the problem we know that:



Lets replace those values in our equation to find

:




We can conclude that after 1600 years of radioactive decay, the mass of the 100-gram sample will be
91.7 grams.
The two points where they end and the point where they start form a right triangle, one leg is 12, the other leg is 15, you need to find the hypotenuse.
use the Pythagorean theorem: 12²+15²=c²
c≈19
they are about 19 feet apart.
Answer:
The focus of the parabola is at the point (0, 2)
Step-by-step explanation:
Recall that the focus of a parabola resides at the same distance from the parabola's vertex, as the distance from the parabola's vertex to the directrix, and on the side of the curve's concavity. In fact this is a nice geometrical property of the parabola and the way it can be constructed base of its definition: "All those points on the lane whose distance to the focus equal the distance to the directrix."
Then, the focus must be at a distance of two units from the vertex, (0,0), on in line with the parabola's axis of symmetry (x=0), and on the positive side of the y-axis (notice the directrix is on the negative side of the y-axis. So that puts the focus of this parabola at the point (0, 2)
Answer:
D
Step-by-step explanation:
let y = f(x), that is
y = 
Rearrange making x the subject
Multiply both sides by 5
5y = 2x - 3 ( add 3 to both sides )
5y + 3 = 2x (divide both sides by 2 ) , then
x = 
Change y back into term of x, hence
(x) =
→ D