The 2 equations are
18.20x+19.50y=230.10
and
x+y=12
where x is the months of original cost and y is months for new cost. Since you know that you paid for one year (12 months) you can make the second equation. Then you want to substitute the first equations x by making the second equation
x=(12-y)
18.20(12-y)+19.50y=230.10
218.40-18.20y+19.50y=230.10
1.30y=11.70
y=9
so that means you had the original rate for 3 months and the new one for 9 months
Answer:
An average of about 450 hours; You could say something along the lines of "If the pianist who practices an average of 45 hours per week practices everyday for three months, they would play for approximately 450 hours total."
Step-by-step explanation:
We could write an equation to make it simpler to figure out, making the number of hours after three months = n, 4 = weeks in a month, 3 = the number of months, and 45 = the number of hours after a week. As an equation, it would look like:
45 * 3 * 4 = n
We know 3 *4 is 12, so the equation becomes 45 * 12 = n.
45 * 12 = 540, therefore the pianist practices an average of approximately 540 hours over a three-month period of time.

so... you tells us, which filling rate is the bigger and thus faster one?
Answer:
Step-by-step explanation:
N is 3 bc #of terms minus 1
Exponents go from 3>2>x>none
Can be factored using binomial theorem