Question

To save money, you put $200 in your bank account each week. After saving for 4 weeks, you have $1,700 dollars in your account. Which equation models your savings account balance at the end of each week?
y – 4 = 200(x – 1,700)
y – 200 = 1,700(x – 4)
y – 1,700 = 200(x – 4)
y – 1,700 = 200(x + 4)
Mathematics

Answer 1

the third choice y-1700=200(x-4)

Answer 2

Answer: $y-1700=200(x-4)$

Step-by-step explanation:

Given: To save money, you put $200 in your bank account each week.

⇒d=200

After saving for 4 weeks, you have $1,700 dollars in your account.

⇒$a_4=1700$

Let $a_1$ be the initial amount in the bank.

then,

$a_4=a_1+3d\\\Rightarrow\ a_1=a_4-3d$

Now, Let x be the number of weeks and y be the savings account balance at the end of each week

then by Arithmetic Progression

$y=a_1+d(x-1)\\\Rightarrow\ y=(a_4-3d)+d(x-1)\\\Rightarrow\ y=a_4-3d+dx-d\\\Rightarrow\ y-a_4=dx-4d\\\Rightarrow\ y-a_4=d(x-4)$

Substitute the values of $d=200\ and\ a_4=1700$ in above equation we get,

$y-1700=200(x-4)$