The equation of the circle:

(h, k) - center
r - radius
We have:

Substitute:

Answer:
25%
Step-by-step explanation:
Price reduction = 20 - 15 = $ 5
Percent decrease of price = (5/20)*100 = 5*5 = 25%
Answer:
x < 4
Step-by-step explanation:
We have that: 1 + 2x < 9. Let's solve this as if the < sign was an = sign:
1 + 2x < 9
Isolate the variable:
2x < 9 - 1
2x < 8
Divide by 2:
x < 8/2
x < 4
The answer is x < 4.
5% of $50 = 5/100 x 50 = $2.50
Total = 50 + 2.50 = $52.50
The saes tax is $2.50; her total cost of the shirt is $52.50