Answer:
x = -5
y = 6
Step-by-step explanation:
3x + 7y = 27 --------------(I)
-3x + y = 21 -----------(II)
Add equation (I) & (II) and so x will be eliminated and we can find the value of y.
(I) 3x + 7y = 27
(II) <u> -3x + y = 21 </u> {add}
8y = 48
y = 48/8
y = 6
Plugin y = 6 in equation (I)
3x +7*6 = 27
3x + 42 = 27
3x = 27 - 42
3x = -15
x = -15/3
x = -5
Answer:
1. 1343 years
2. 9 hours
3. 39 years
Step-by-step explanation:
1. Given, half-life of carbon = 5730 years.
∴ λ = 0.693/half-life of carbon = 0.693/5730 = 0.000121
If N₀ = 100 then N = 85
Formula:- N = N₀*e^(-λt)
∴ 85 = 100 * e^(-0.000121t)
∴㏑(-0.85)=-0.000121t
∴ t = 1343 years
2. Given half-life of aspirin = 12 hours
λ = 0.693/12 = 0.5775
Also N₀ = 100 then 70 will disintegrate and N = 30 will remain disintegrated.
∴ 70 = 100 *e^(-0.05775t)
0.70 = e^(-0.05775t)
㏑(0.70) = -0.05775t
∴ t = 9 hours
3. The population of the birds as as A=A₀*e^(kt)
Given that the population of birds fell from 1400 from 1000, We are asked how much time it will take for the population to drop below 100, let that be x years.
The population is 1400 when f = 0, And it is 1000 when f = 5
We can write the following equation :
1400 = 1000e^(5t).
∴1400/1000 = e^(5k)
∴ k = ㏑(1.4)/5
We need to find x such that 1400/100 = e^(xk)
14 = e^(xk)
∴ x = 39 years
Answer:
Not quite sure what you're meant to solve for, but my solution is below.
Step-by-step explanation:
The square root of a value squared is the absolute value of that value, because squaring removes all negatives. Therefore:
Hope this helps!
78
step by step explanation:
first: divide 600 and 15
answer to 600/15: 40
second: divide 3120 and 40
final answer: 78
Answer:
What is the question?
Step-by-step explanation:
We need to know what problem to solve with the information provided.
