dont know this, giving medal..

The sales tax in one state is 7%. Write a function rule for finding the total cost of an item with selling price x. Then find the total cost of a CD player with a selling price of $150.
a.
f(x) = x – 7; $148.93
c.
f(x) = 7 + x; $151.07
b.
f(x) = 0.07x; $10.50
d.
f(x) =1.07x; $160.50

Question

dont know this, giving medal..


The sales tax in one state is 7%. Write a function rule for finding the total cost of an item with selling price x. Then find the total cost of a CD player with a selling price of $150.
a.
f(x) = x – 7; $148.93
c.
f(x) = 7 + x; $151.07
b.
f(x) = 0.07x; $10.50
d.
f(x) =1.07x; $160.50

anonymous · Answer

tax you need to pay = 7% of the selling price = 7% x = 0.07x
Total cost of the item = price of item + tax paid
                                   =x +  0.07x 
                                   = (add the terms yourself, can you?)

Once you get the equation. put x= 150 into the equation. and work out the total cost yourself.
Can you first try it?