Question 1200570
the TVs are on sale for 25% off.
your coupon gives you $100 off the price of a TV.
if you are talking about the same TV, then $100 is equal to 25% of the price of the TV.
divide 100 by .25 to find that the original price of the TV would have to be  $400.
$400 minus $100 = $300
$400 - .25 * $400 = $400 - $100 = $300.


algebraicaly, you would have two equation that need to be solved simultaneously that would look like this.
y = x - .25 * x which is simplified to y = .75 * x is your first equation.
your second equation would be y = x - 100
these two equations would need to be solved simultaneously.
they are:
y = .75 * x
y = x - 100


since they are both equal to the same value of y, set them equal to each other to get:
.75 * x = x - 100
subtract .75 * x from both sides of the equation and add 100 to both sides of the eqution to get:
100 = .25 * x
solve for x to get:
x = 400


x is the original price of the TV.
.75 * 400 = 300
400 - 100 = 300


it all checks out.
your solution is x = 400 which is the original price of the TV.