9514 1404 393
Answer:
a) 600
b) see below
c) 1.26 hours
Step-by-step explanation:
a) The value of y when x=0 is the coefficient of the exponential term:
y = 600·3^(-0) = 600·1 = 600
There were 600 atoms to start.
__
b) see attached for a graph
__
c) The graph shows 150 atoms at t = 1.26, about 1.26 hours after the start of time counting.
If you want to find that value algebraically, substitute for y and solve for x. Logarithms are involved.
150 = 600·3^(-x)
150/600 = 3^(-x)
log(1/4) = -x·log(3)
x = -log(1/4)/log(3) = log(4)/log(3) ≈ 1.2618595
After about 1.26 hours, there were 150 atoms.
It shoukd be A if im not mistaken
Answer:
b = a + 2 or b = 2 - a
Step-by-step explanation:
Solve for b:
-4 + a^2 + 4 b - b^2 = 0
The left hand side factors into a product with two terms:
(2 + a - b) (-2 + a + b) = 0
Split into two equations:
2 + a - b = 0 or -2 + a + b = 0
Subtract a + 2 from both sides:
-b = -a - 2 or -2 + a + b = 0
Multiply both sides by -1:
b = a + 2 or -2 + a + b = 0
Subtract a - 2 from both sides:
Answer:
b = a + 2 or b = 2 - a
Yes...thats what u want to do. you want to get the x terms on one side and everything else on the other side.
8x = 7x + 3....so we will subtract 7x from both sides
8x - 7x = 7x - 7x + 3....simplify
1x, or just x = 3 (because ur 7x's cancelled each other out)
so ur answer is : x = 3
and u can check ur answer by subbing it back into the original equation.
8x = 7x + 3
8(3) = 7(3) + 3
24 = 21 + 3
24 = 24 (correct)