Please help. George purchased a concert ticket on a web site. The original price of
the ticket was $85. He used a coupon code to receive a 15% discount.
The website applied a 10% service fee to the discounted price. George's
ticket was less that the original price by what percent?
15%
10%
6.5%
8.5%

6.5%

Step-by-step explanation:

The original price of the ticket was 100% of the price of the ticket.

The 15% coupe reduced the price to 85% of the price of the ticket.

The 10% fee on the discounted price adds 10% of 85% to 85%, so it adds 8.5% to 85%. By adding the fee he is at 93.5% of the original price.

100% - 93.5% = 6.5%

The overall percent off compared to the original price was 6.5%.

6.5%

for this case we have by definition, if two lines are perpendicular, then the product of their slopes is -1.

then, given the following line:

so,

we are looking for m_ {2}:

then, the line is given by:

we find "b" replacing the given point:

finally, the equation is:

option c

thats not a system of equations, that is a solution