Question 580693
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.
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Assign the give values as follows:
x1=3; y1=10
x2=11; y2=26
Find the slope using the slope formula; m = {{{(y2-y1)/(x2-x1)}}}
 m = {{{(26-10)/(11-3)}}} = {{{16/8}}} = 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
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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.
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Assign the given values as follows:
x1 = 1.35; y1 = 4820
x2 = 1.40; y2 = 3885
find the slope
m = {{{(3885-4820)/(1.40-1.35)}}} = {{{(-985)/.05}}} = -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
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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.
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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