Answer:
187.5 gallons
Step-by-step explanation:
Make a proportion
= 
3000/16 = 187.5, so multiply 1 by 187.5 to find the gallons used in a year
This gets you 187.5 gallons used in a year
1. Write the equation:
d(-3 + x) = kx + 9
2. "Open" the parenthesizes:
-3d + dx = kx + 9
3. Take kx to the left side, -3d to the right, everything with different sign (+ replace with - when transferring, - replace with +):
dx - kx = 9 + 3d
4. Factor x in the left side:
x(d - k) = 9 + 3d
5. Finally, divide the whole equation by (d - k):
x = (9 + 3d)/(d - k)
That's the final answer. Good luck!
To solve any equation, you do whatever you need to do
to wind up with the unknown quantity all alone on one side.
BUT ... whatever you do to one side of the equation, you must
also do to the other side.
Here, we have the
he original equation: -15 = a/5
Multiply each side by 5 : -75 = a
and bada-bing, THERE's the solution !
Answer:

Step-by-step explanation:
We're going to have to work backwards.
The sum of 4 and k is
.
Half is simply that divided by 2.

Now, we'll subtract 8 from it.

Bam!