
Hope you could get an idea from here.
Doubt clarification - use comment section.
Answer:
$675
Step-by-step explanation:
Let
x = original price of laptop
Discount = 10%
Actual price paid = x - 10% of x
= x - .10x
= .90x
Cost of mouse = $13.99
Total amount paid = $621.49
Total amount paid = actual cost of laptop + Cost of mouse
621.49 = .90x + 13.99
621.49 - 13.99 = .90x
607.5 = .90x
x = 607.5 / .90
= 675
Original cost of the laptop = $675
<u>Answer:</u>
<em><u>w = -19</u></em>
<em><u></u></em>
<u>Explanation:</u>
To solve this equation, subtract ten from both sides. This will isolate the variable (w) and allow us to find its value.

If you would like to double check that the variable (w) does in fact equal negative nineteen, substitute the value of the variable in the equation and solve.
![10 + w = -9\\10 + -19 = -9\\-19 = -19 [true]](https://tex.z-dn.net/?f=10%20%2B%20w%20%3D%20-9%5C%5C10%20%2B%20-19%20%3D%20-9%5C%5C-19%20%3D%20-19%20%5Btrue%5D)
Therefore, the value of w in the given equation is <em><u>-19.</u></em>