Answer:
The original cost of the DVD was $21`.59
Step-by-step explanation:
In order to find this, you first must note that the new price is 88% of the older price. We get this since there was a subtraction of 12%.
Now knowing that, we can divide the new price by the percentage paid and it will give us the original price.
$19/88% = Original Cost
19/.88 = Original Cost
$21.59 = Original Cost
Ok so first, write down the equation. We know that x=3 and y=4. You just basically plug in the terms into the variables. So it would be 3(3)+1/4(4)^2. Simplify that equation and you should get your answer :)
Simplify
4ax+12-3ax=25+3a
ax+12=25+3a
ax-3a=25-12
a(x-3)=13