Answer: 132.54
Step-by-step explanation:
First you divide the circumference by two pi then you divide that by two to get the radius next you multiply first you divide the circumference by two pi then you divide that by two to get the radius next you Square that total then the last step is to multiply that by .75 or 3/4.
Simplifying
x + 0.7 = 1 + -0.2x
Reorder the terms:
0.7 + x = 1 + -0.2x
Solving
0.7 + x = 1 + -0.2x
Solving for variable 'x'.
Move all terms containing x to the left, all other terms to the right.
Add '0.2x' to each side of the equation.
0.7 + x + 0.2x = 1 + -0.2x + 0.2x
Combine like terms: x + 0.2x = 1.2x
0.7 + 1.2x = 1 + -0.2x + 0.2x
Combine like terms: -0.2x + 0.2x = 0.0
0.7 + 1.2x = 1 + 0.0
0.7 + 1.2x = 1
Add '-0.7' to each side of the equation.
0.7 + -0.7 + 1.2x = 1 + -0.7
Combine like terms: 0.7 + -0.7 = 0.0
0.0 + 1.2x = 1 + -0.7
1.2x = 1 + -0.7
Combine like terms: 1 + -0.7 = 0.3
1.2x = 0.3
Divide each side by '1.2'.
x = 0.25
Simplifying
x = 0.25
I only know 1 way.
EXPLANATION:
-To formulate an equation, you must first know what data the exercise gives us to locate them correctly.
data:
-6 that must be added to a number.
-four times a number that is equal to 4x
-a result that is equal to 50
Now with these data we formulate the equation:
if we solve the equation we have:
Answer:
Ok, an exponential decay is written as:
P(t) = A*(1 - r)^t
Where A is the initial population, r is the rate of decay and t is the unit of time.
We know that the initial population is 15g
then:
P(t) = 15g*(1 - r)^t
And at t = 3hs, the populations is 5g
P(5h) = 5g = 15g*(1 - r)^5
5/15 = 1/3 = (1 - r)^5
(1/3)^(1/5) = (1 - r) = 0.8
Now, the half life time of the sustance is t = x, such that the population reduces to it's half:
P(x) = A/2 = 15g/2 = 7.5g
Then:
7.5g = 15g*0.8^x
7.5g/15g = 1/2 = 0.8^x
Now, remember that if we have:
a = b^x
then
x = ln(a)/ln(b)
ln(1/2)/ln(0.8) = x = 3,11 hours
1 thousand and 1 hundred means 1100.
In scientific notation, it's 1.1*10^3
