The answer is 28 years
At = A0 * e^(-k * t)
At = 12 g
A0 = 15 g
k = 7.9 × 10^-3 = 0.0079
t = ?
12 = 15 * e^(-0.0079 * t)
12/15 = e^(-0.0079 * t)
0.8 = e^(-0.0079 * t)
Logarithm both sides (because ln(e) = 1:
ln(0.8) = ln(e^(-0.0079 * t))
ln(0.8) = (-0.0079 * t) * ln(e)
-0.223 = -0.0079 * t
t = -0.223 / -0.0079
t = 28.23
t ≈ 28 years
Answer:
3 feet
Step-by-step explanation:
A 12-foot ladder is leaning across a fence and is touching a higher wall located 3 feet behind the fence. The ladder makes an angle of 60 degrees with the ground.
ladder is 12 foot
The ladder makes an angle of 60 degrees with the ground.
It form a right angle triangle . ladder is the hypotenuse


multiply 12 on both sides
x= 6
the distance from the base of the ladder to the bottom of the fence
x-3 = 6-3=3 feet
Answer:

Step-by-step explanation:
The equation of any line in slope-intercept form is:
y=mx+b
Being m the slope and b the y-intercept.
Assume we know the line passes through points A(x1,y1) and B(x2,y2). The slope can be calculated with the equation:

Two points are given: (-6,4) and (-2,2). Calculating the slope:

The equation of the line is, so far:

To calculate the value of b, we use any of the given points, for example (-6,4):


Solving:
b = 1
The equation of the line is:

We can see none of the choices is correct.