SOLUTION: I Really Need Your HELP with these Problems. I will be so thankful if you could HELP ME, Please...! I know how to solve the linear equations but I have a problem to write them in

Click here to see ALL problems on Linear-equations

Question 580693: I Really Need Your HELP with these Problems. I will be so thankful if you could HELP ME, Please...! I know how to solve the linear equations but I have a problem to write them in correct form, from the word problem.
Ps. (I already send these problems but in the first problem in the answer b) i put the wrong sign, now everyth is corrected. thank you)
Problem 1:
(Ps.proffesor gave us these answers for this problem and we have to find correct one: a) y=1/2x+17/2 B)y=2x+4 C)y=2x+15 D)y=-2x+16 )
1. A faucet is used to add water to a large bottle that already contained some water. After it has been filling for 3 seconds, the gauge on the bottle indicates that it contains 10 ounces of water. After it has been filling for 11 seconds, the gauge indicates the bottle contains 26 ounces of water. Let Y be the amount of water in the bottle X seconds after the faucet was turned on. Write a linear equation that models the amount of water in the bottle in terms of X.

2. Problem 2
A gas station sells 4820 gallons of regular unleaded gasoline in a day when they charge $1.35 per gallon, whereas they sell 3885 gallons on a day that they charge $1.40 per gallon. Find a linear equation that relates gallons sold to proce. Use this equation to predict the number of gallons sold at a price of $1.22 per galon.
(the answer should be 7251 gal, but I do not know how to put this together in order to have the answer)

Problem 3.
The projected U.S long-distance revenue (in billions of dollars)from 1999 to 2004 is given by the equatoin, y=3x+111 where X is the number of years 1999. Graph this equation and use it to estimate the amount of long-distance revenue in 2007.
(ps, you do not have to send me the graph cos I will know how to graph this, the answer should be $135 billion. Again, I do not know how to put this together
Answer by ankor@dixie-net.com(22740) (Show Source):
You can put this solution on YOUR website!
1. A faucet is used to add water to a large bottle that already contained some water.
After it has been filling for 3 seconds, the gauge on the bottle indicates that it contains 10 ounces of water.
After it has been filling for 11 seconds, the gauge indicates the bottle contains 26 ounces of water.
Let Y be the amount of water in the bottle X seconds after the faucet was turned on.
Write a linear equation that models the amount of water in the bottle in terms of X.
:
Assign the give values as follows:
x1=3; y1=10
x2=11; y2=26
Find the slope using the slope formula; m =
m = = = 2 is the sloe
Find the equation using the point/slope formula; y - y1 = m(x - x1)
y - 10 = 2(x - 3)
y - 10 = 2x - 6
y = 2x - 6 + 10
y = 2x + 4, is the linear equation
:
:
2. Problem 2
A gas station sells 4820 gallons of regular unleaded gasoline in a day when they charge $1.35 per gallon, whereas they sell 3885 gallons on a day that they charge $1.40 per gallon.
Find a linear equation that relates gallons sold to price.
:
Assign the given values as follows:
x1 = 1.35; y1 = 4820
x2 = 1.40; y2 = 3885
find the slope
m = = = -18700 is the slope
y - 4820 = -18700(x - 1.35)
y - 4820 = -18700x + 25245
y = -1800x + 25245 + 4820
y = -18700x + 30065, is the equation
"predict the number of gallons sold at a price of $1.22 per gallon."
y = -18700(1.22) + 30065
y = -22814 + 30065
y = 7251 gal
:
:
Problem 3.
The projected U.S long-distance revenue (in billions of dollars)from 1999 to 2004 is given by the equation, y=3x+111 where X is the number of years 1999.
Graph this equation and use it to estimate the amount of long-distance revenue in 2007.
:
From 1999 to 2007, is eight yrs, therefore x=8, replace x in the given equation
y = 3(8) + 111
I'm sure you can do this