20x20=400
pi(3.14) x 10^2(100)
100x3.14=314
400-100pi=85.8407 (then you can round if you need to)
Answer:
A = -12, B = 9 and C = .2
Step-by-step explanation:
So it just looks like we need to use algebra to move everything around to get it in the form Ax + By = C
So, let's start with 9y = 12x + 0.2. From standard form we have all terms wth variables on one side, so let's do that. the right sie has both a variable term and non variable term, so let's get rid of the variable term. The variable term is 12x, so to get rid of it you subtract 12x from both sides.
9y = 12x + 0.2
9y - 12x = 0.2
To make it exactly in standard form just rarrnge.
-12x + 9y = 0.2
So now we have A = -12, B = 9 and C = .2
Answer:
Use the value for the variable to solve for the other unknowns. Substitute the value for the variable into the expression for the number of seats on the middle level. Substitute the value for the variable into the expression for the number of seats on the lower level.
Answer:
Area = 64π
Area \: = \pi {r}^{2}Area=πr
2
64 \: \pi \: = \pi {r}^{2}64π=πr
2
{r}^{2} = \dfrac{64\pi}{\pi}r
2
=
π
64π
{r}^{2} = 64r
2
=64
r \: = \: \sqrt{64} = 8r=
64
=8
Radius = 8 units
Finding the Diameter -
Diameter = Radius x 2 = 8 x 2 = 16 .
\bold{Diameter \: is \: 16 \: units}Diameteris16units
If the radio active isotope has the half life of 24100 years, then the initial quantity is 2.16 grams
The half life in years = 24100
Consider the quantity of the radio active isotope remaining
y = 
When t = 1000 the y = 1.2
y = C/2 when t = 1599
Substitute the values in the equation
C/2 = 
Cancel the C in both side
1/2 = 
Here we have to apply ln to eliminate the e terms
ln (1/2) = 24100k
k = ln(1/2) / 24100
k = -2.87× 10^-5
To find the initial value we have to substitute the value of k and y in the equation
1.2 = Ce^{1000 × -2.87× 10^-5}
C = 1.2 / e^(-0.0287)
C = 2.16 gram
Hence, the initial quantity of the radioactive isotope is 2.16 gram
Learn more about half life here
brainly.com/question/4318844
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