Answer:
Step-by-step explanation: is b
Answer:
your answer would be 7285.63
Answer: A) 
B) H = 5.10
C) Yes
Step-by-step explanation: <u>Exponential</u> <u>Decay</u> <u>function</u> is a model that describes the reducing of an amount by a constant rate over time. Generally, it is written in the form: 
A) C is initial quantity, in this case, the initial concentration of DDT. To determine r, using the data given:



Using a natural logarithm property called <em>power rule:</em>



The decay function for concentration of DDT through the years is 
B) The value of H is calculated by 


Again, using power rule for logarithm:



H = 5.10
Constant H in the half-life formula is H=5.10
C) Using model
to determine concentration of DDT in 1995:

y(24) = 0.5
By 1995, the concentration of DDT is 0.5 ppm, so using this model is possible to reduce such amount and more of DDT.
Answer:
1. 3
2. 2
3. 2
4. 6
5. No solution
Step-by-step explanation:
2x+3y=8 (1)
-6x+4y=11 (2)
3(1) + (2)
6x + 9y = 24
-6x + 4y = 11
13y = 35
y = 35/13
x = -1/26
3x-y=3 (1)
-2x+2y=6 (2)
2(1) + (2)
6x - 2y = 6
-2x + 2y = 6
4x = 12
x = 3
y = 3(3) - 3 = 6
3x+4y=-10 (1)
5x-2y=18 (2)
(1) + 2(2)
3x + 4y = -10
10x - 4y = 36
13x = 26
x = 2
5x-2y=3 (1)
2x-y=0 (2)
(1) - 2(2)
5x - 2y = 3
-4x + 2y = 0
x = 3
2(3) - y = 0
y = 6
3x+2y=10 (1)
6x+4y=14 (2)
2(1) - (2)
6x + 4y = 20
6x + 4y = 14
0 = 6 is a false statement so no solution
CosP=sinQ
cosQ=sinP
Thus cosP=4/5 and cosQ=3/5 so the sum is 7/5