2 figures are congruent if at least 2 sides are the same length, there angles are the same, etc
Answer:
The initial mass of the sample was 16 mg.
The mass after 5 weeks will be about 0.0372 mg.
Step-by-step explanation:
We can write an exponential function to model the situation.
Let the initial amount be A. The standard exponential function is given by:

Where r is the rate of growth/decay.
Since the half-life of Palladium-100 is four days, r = 1/2. We will also substitute t/4 for t to to represent one cycle every four days. Therefore:

After 12 days, a sample of Palladium-100 has been reduced to a mass of two milligrams.
Therefore, when x = 12, P(x) = 2. By substitution:

Solve for A. Simplify:

Simplify:

Thus, the initial mass of the sample was:

5 weeks is equivalent to 35 days. Therefore, we can find P(35):

About 0.0372 mg will be left of the original 16 mg sample after 5 weeks.
Hello from MrBillDoesMath!
Answer:
The first choice ( -12, 20)
Discussion:
Using matrix multiplication we find the equations:
1x + 1y = 8 (A)
2x + 3y = 36 (B)
Next, compute
2(A) - B =>
(2x + 2y) - (2x + 3y) = 2*8 - 36 =>
(2x - 2x) + ( 2y-3y) = 16 - 36 =>
-y = -20 =>
y = 20
Substituting this y value in (A) gives
x + 20 = 8 =>
x = 8 - 20 =>
x = -12
The answer is the first choice ( -12, 20)
Thank you,
MrB
4 of a 10 because there is 4 blue marbles and 6 yellow