a. Remember that f(x) is the amount of money you earned each week. Also note that teddybears = x
<em>f(x) = 5x + 300</em> is your equation
5x + 300 is your expression
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b. A reasonable domain can be 0 < x < 50, in which x is the amount you sell. 50 is a bit far out, but it takes into account holidays, as well as places you may sell at that have large amount of people.
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c. f(20) means that you sold 20 teddy bears, as 20 replaces x, which (like what was stated above) is the amount you sell
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d. Plug in 25 for x.
5x + 300 = t (total amount you make)
5(25) + 300 = t
Remember to follow PEMDAS. First, multiply 5 with 25
5 x 25 = 125
Next, add
125 + 300 = t
t = 425
$425 is the amount you make in a week.
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e. Note that you make $425 if you sell 25 teddy bears. Also remember that you are paid a flat $300. Remember the formula:
f(x) = 5x + 300
Plug in 425 for f(x)
425 = 5x + 300
Isolate the x. Do the opposite of PEMDAS. Note the equal sign. What you do to one side, you do to the other.
First, subtract 300 from both sides
425 (-300) = 5x + 300 (-300)
425 - 300 = 5x
125 = 5x
Next, divide 5 from both sides
(125)/5 = (5x)/5
x = 125/5
x = 25
25 teddy bears must be sold
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hope this helps
