David wants to buy a new tablet computer. He looks at a sales ad and sees that a computer store is selling a tablet computer for $499 which is 13

off the regular price.

Part A:

Write an equation that represents the situation. Let x = the original cost of the tablet.

Part B:

Find the original cost of the tablet computer

Part A: x - $13 = $499

Part B: The original cost is $512

Step-by-step explanation:

PART A:

If the discounted price is $499 and the discount is $13, the the original price (x) minus the discount ($13) equals the discounted price ($499).

Hence, x - $13 = $499.

PART B:

In order to find the original price (x) add the discount ($13) to the discounted price ($499). To do this, set the equation in Part A equal to x by add $13 to both sides.

x - $13 = $499

x - $13 + $13 = $499 + $13

Then add $499 and $13 to get $512.

x = $499 + $13

x = $512

Original cost = $573.56

Step-by-step explanation:

Let x be the original cost of the tablet

13% of x = discount

New selling price = 499 = x - (13% of x)

499 = x - 0.13x = 0.87x

x = 499/0.87 = $573.56