Start by writing a formula, where is Brad's purchase price and is the original price.
Subtract from both sides.
Multiply both sides by .
This equation in numbers:
(-8x)^6 • (4x)^2
(262144•x^6) • (16x^2)
4,194,304x^8
It’s $18.63 , 10.35 divided by 5 = 2.07 , so 2.07 times 9 = $18.63