Ifound a place that would give me a 20% discount if spend over $50. my bill is $75. what is my final bill after the savings

Okay. So, your bill is $75. But since you spent over $50, you get a 20% discount. You get a 20% discount, but you still have to pay 80% of the price. To find the bill after the savings, multiply 75 by 80% (0.8). 75 * 0.8 is 60. Your final bill after the savings is $60.

The first step would be to create an equation to find the discount amount. 
$75.00 × 0.20 = $15.00

The discount amount would be $15.00. But we are not done! The last step would be to subtract the discount from the original price. 
$75.00 - $15.00 = $60.00

Your answer would be $60.00 or $60. 

I hope this helps!

Horizontal change or the change of x

If your asking how much altogether for 12 performance the answer will be 98,496.