In February, you have a balance of $270 in your bank account. Each month you deposit $45. Let January = 1, February = 2, and so on. Write an equation for this situation. Use the equation to find the balance in June.
y – 270 = 45(x – 2) ; $450
y = 45(x – 4); $270
y = 45(x – 4); $180
y – 270 = 45x; $45
2007-07-08 08:19:30 · 5 answers · asked by Chealsea Y 1 in Science & Mathematics ➔ Mathematics
Let the balance in month x be $y.
Then:
When x = 1, y - 270 = -1*45
When x = 2, y - 270 = 0*45
When x = 3, y - 270 = 1*45
When x = 4, y - 270 = 2*45
In general, in month x: y - 270 = 45(x - 2).
In June, x = 6, and
y - 270 = 45(6 - 2)
y = 270 + 270 - 90
y = 540 - 90
y = 450.
The balance in June is $450.
The first answer is correct.
2007-07-08 08:33:31 · answer #1 · answered by Anonymous · 0⤊ 0⤋
Sloppy problem wording! WHEN do I deposit? Feb. 1? Feb. 28? I'm going to assume that they meant to say " at THE END OF February. The problem therefore begins with a March deposit.
The beginning point is (2,270)
2=Feb., 270 is amount on hand
3= 270+45, =(3, 315)
4= 270+45+45 =(4, 360)
5 = 270 + 45+45+45 = (5,405)
6= 270 + 45+45+45+45=(6,450)
If you plotted this you would get a straight line
The slope is 45, x is the month, y is the bank balance
Your equation is y = 45(x-2) +270
2007-07-08 09:04:02 · answer #2 · answered by Grampedo 7 · 0⤊ 0⤋
Simply from process of elimination, A is the answer. You are depositing 45/month in the bank and you are leaving the initial 270 in the account. Therefore, your balance can never drop below 270. Therefore, you only have one option that is over 270, which is A.
2007-07-08 08:25:14 · answer #3 · answered by redheadedwonder11 2 · 0⤊ 0⤋
The first one
y=270+45(x-2) $450
2007-07-08 08:25:10 · answer #4 · answered by santmann2002 7 · 0⤊ 0⤋
270 +45(n - 1) where n is number of the month
2007-07-08 08:26:20 · answer #5 · answered by spirit dummy 5 · 0⤊ 0⤋