Answer:
3000
Step-by-step explanation:
a decrease in the ratio 5:3 implies that:
new quantity :old quantity :5:3
let new quantity be x.
x:1800=5:3
x/1800=5/3
3x=9000
x=9000/3
x=3000
Answer:
To know if it is a function see if there are two of the same x-intercept( which makes a vertical line). If there is,then it is not a function.
Answer:

Step-by-step explanation:
Let's rewrite the left side keeping in mind the next propierties:


Therefore:

Now, cancel logarithms by taking exp of both sides:

Multiply both sides by
and using distributive propierty:

Substract
from both sides and factoring:

Multiply both sides by -1:

Split into two equations:

Solving for 
Add 4 to both sides:

Solving for 
Collect in terms of x and add
to both sides:

Divide both sides by e-2:

The solutions are:

If we evaluate x=4 in the original equation:

This is an absurd because log (x) is undefined for 
If we evaluate
in the original equation:

Which is correct, therefore the solution is:

Answer:
C
Step-by-step explanation:
Perpendicular lines have slopes which are the negative reciprocal of each other. To find the slope, convert 3x-5y=8 into y=mx+b form.
3x-5y=8
-5y = -3x +8
y = 3/5 x - 8/5
The slope is 3/5 so its perpendicular slope is -5/3. Write the equation of this line through the point (3,7) using point slope form. Then simplify into y=mx+b form.
