Answer:
Step-by-step explanation:
30 = -5(6n + 6)...distribute the 5 thru the parenthesis
30 = -30n - 30....add 30 to both sides
30 + 30 = -30n
60 = -30n....divide both sides by -30
-60/30 = n
-2 = n <===
Answer:
85%
Step-by-step explanation:
9+51 = 60
(51/3) ÷ (60/3) = 17/20
(17/20)% = 85%
The answer is 28 years
At = A0 * e^(-k * t)
At = 12 g
A0 = 15 g
k = 7.9 × 10^-3 = 0.0079
t = ?
12 = 15 * e^(-0.0079 * t)
12/15 = e^(-0.0079 * t)
0.8 = e^(-0.0079 * t)
Logarithm both sides (because ln(e) = 1:
ln(0.8) = ln(e^(-0.0079 * t))
ln(0.8) = (-0.0079 * t) * ln(e)
-0.223 = -0.0079 * t
t = -0.223 / -0.0079
t = 28.23
t ≈ 28 years
4 x U(unit price) = $43.80
U = 43.80 / 4
U = 10.95$
7 x 10.95 = 76.65$
