The anwser to your problem is 1,800
To find the average rate of change in a interval

We use the following formula:

Applying this to our interval

We have the following rate of change:

We have an average rate of change equals to 6.
10b=200
10/10=1
200/10=20
B=20 inches
Hope this helped!
Answer:
It will take 5 weeks for you and your friend to have the same balance
Step-by-step explanation:
Let
Your savings expression be
135 + 12x
Your friends savings expression
95 + 20x
Where,
x = number of weeks for you and your friend to have the same balance
Equate the two expressions
135 + 12x = 95 + 20x
Collect like terms
135 - 95 = 20x - 12x
40 = 8x
Divide both sides by 8
40/8 = x
x = 40/8
= 5
x= 5 weeks
Check
Your savings expression
135 + 12x
135 + 12(5)
=135 + 60
= $195
Your friends savings expression
95 + 20x
95 + 20(5)
= 95 + 100
= $195
Therefore, It will take 5 weeks for you and your friend to have the same balance