Answer:
(6,-7)
Step-by-step explanation:
subtract them:
-8x - 5y = -13
-4x - 5y = 11
you get
-4x = -24
so x = 6
plug x into the second equation:
-24 - 5y = 11
-5y = 35
y = -7
so your solution is (6,-7).
Answer: 4 7/12 cups of popcorn
Step-by-step explanation:
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:
Step-by-step explanation:
The point of this question is to find out the point where two lines intersect. First we need to get the equation of those lines
Slope of line 1:
(Yb -Ya)/(Xb - Xa) =
(-10 - (-14))/(-1 - (-3)) =
4/2 =
2
Use that slope to find the Y-intercept of line 1
y = 2x + b
-14 = 2(-3) +b
-14 = -6 + b
-8 = b
Therefore Line 1 is:
y = 2x - 8
Slope of line 2
(11 - 13)/(-1 - (-3)) =
-2/2 =
-1
Y-intercept of line 2
y = -x + b
13 = -(-3) +b
13 = 3 + b
10 = b
Therefore line 2 is
y = -x + 10
Now we have 2 equations to solve for the coordinates x and y
y = 2x - 8
y = -x + 10
Substitute y out in one of the equations
2x - 8 = -x + 10
3x = 18
x = 6
Plug x into one of the equations
y = 2(6) - 8
y = 12 - 8
y = 4
Therefore the solution is:
x=6, y=4
