Answer:
A = 120 cm²
Step-by-step explanation:
The 4 part of the ratio relates to the height of triangle A , then
16 ÷ 4 = 4 cm ← value of 1 part of the ratio, then
5 parts = 5 × 4 cm = 20 cm
The area (A) of triangle B is calculated as
A = 
bh ( b is the base and h the height )
Here b = 12 and h = 20 , then
A = × 12 × 20 = 6 × 20 = 120 cm²
Answer:
Left: The substance is decreasing by 1/2 every 12 years
Right: The substance is decreasing by 5.61% each year
Step-by-step explanation:
exponential decay
A = P(1-r)ᵇⁿ, where A is the final amount, P is the initial amount, r is the rate decreased each time period, b is the number of years, and n is the number of times compounded each year
let's write each formula in terms of this
left:
f(t) = 600(1/2)^(t/12)
matching values up...
A = P(1-r)ᵇⁿ
A = f(t)
P = 600
1 - r = 1/2 -> r = 1/2
t/12 = bn -> b = number of years = t, so bn = b/12 -> n = 1/12. Thus, it is compounded 1/12 times each year, so it is compounded every t*12 = 12 years. If it was compounded each month, it would be compounded 12 times a year
Thus, this is decreasing by a rate of 1/2 each 12 years
right:
f(t) = 600(1-0.0561)^(t)
matching values up...
A = P(1-r)ᵇⁿ
A = f(t)
P = 600
1 - r = 1 - 0.0561 -> r = 0.0561 = 5.61%
t = bn -> b = number of years = t, so bn = b -> n = 1. Thus, it is compounded annually (1 time each year)
Thus, this is decreasing by a rate of 5.61% each year
Use the sine theorem:
sin(angle A) / length of side a = sin (angle B) / lenght of side b
Here:
angle A = 32°
length of side a = length from school to library = x
angle B = 110°
length of side b = 2.2 mi
Then, sin(32°) / x = sin(110°) / 2.2 mi
=> x = 2.2 mi * sin (32) / sin (110)
x = 1.24 mi
Therefore the answer is the option B. 1.2 mi
Answer:
Step-by-step explanation:
see the attached figure to better understand the problem
we know that
----> by angle addition postulate
substitute the given values
