5x + 20 = 90 - a = 90 - (3x + 40)
5x + 20 = 90 - 3x - 40 = 50 - 3x
5x + 3x = 50 - 20
8x = 30
x = 30/8 = 15/4
b = 3(15/4) + 40 = 45/4 + 40 = 51.25
The measure of a supplementary angle is 180 - 51.25 = 128.75
Answer:
D. About 800 years
Step-by-step explanation:
Use the half-life equation:
A = A₀ (½)ⁿ
where A is the final amount,
A₀ is the initial amount,
and n is the number of half-lives.
0.90A₀ = A₀ (½)ⁿ
0.90 = (½)ⁿ
To solve for n, take log of both sides:
log 0.9 = n log 0.5
n = (log 0.9) / (log 0.5)
n = 0.152
It takes 0.152 half-lives. The half-life of carbon-14 is 5730 years.
0.152 × 5730 years = 871 years
The closest answer is D.
Answer:13.333333 repeating
Step-by-step explanation:money divided by how much the games cost
Answer:
the pre-image and the image are congruent
Step-by-step explanation:
The percentage of Change in time is an decrease