A because it’s a binomial
(3 x 10) x 8 = 3 x (10 x 8)
this is called the associative property of multiplication.
it states : (a * b) * c = a * (b * c)
For this case we have an equation of the form:
y = A * (b) ^ t
Where,
A: initial amount
b: decrease rate
t: time in years.
Substituting values we have:
7 = A * (0.5) ^ ((1/20) * t)
For t = 45 years we have:
7 = A * (0.5) ^ ((1/20) * 45)
Clearing A:
A = 7 / ((0.5) ^ ((1/20) * 45))
A = 33.3
Answer:
the density of the substance when it was deposited 45 years ago was:
A = 33.3 milligrams per square centimeter
Answer:
The with and length of the original rectangle are:
width: 20 ft
Length: 30 ft
Step-by-step explanation:
Lets check
Yes, 30 is 10 longer then 20,
the area of the original is 600
if it was 40 and 30 then it would equal 1200