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.
f-¹(x)=
Answer:
Solution given:
f(x)=
Let f(x)=y
y=
Interchanging role of x and y
x=
doing crisscrossed multiplication
x(y+7)=-2y+2
now solve it:
xy+7x=-2y+2
keep like terms in one side
xy+2y=2-7x
take common
y(x+2)=2-7x
make a value of y
y=
So,
f-¹(x)=
Answer:
y = -4x + 2
Step-by-step explanation:
y = mx + b ( slope-intercept)
1. Find Slope:

Lets name 2 as y2 and 10 as y1. And 0 as x2 and 2 as x1.
=
= -4
m/slope = -4
2. Find y-intercept:

2 = -4(0) + b
= 2 = b
Y-intercept/b = 2
3. Put into slope-intercept form:
y = mx + b
= y = -4x + 2
Hope that helps! :D