Answer:

Step-by-step explanation:
This is because the centre is at (3,2) and the radius of the circle is 4 and you square all the terms to find the equation of the circle.
Answer:
3 hours
Step-by-step explanation:
let x = # of hours
Amy: y = 25 + 15x
Dan: y = 10 + 20x
Set the expressions equal to each other and solve for x
10 + 20x = 25 + 15x
20x = 15 + 15x
5x = 15
x = 3
Yes, I believe they are equivalent because if you were to solve -1/4(10t-15) it would equal -2t+3