Question

Patterns, Function and Algebra

Sue had 700 dollars in the bank on January 1. She deposits 30 dollars every week. Tom has 900 dollars in the bank and withdraws 20 dollars every week. In how many weeks will Sue’s amount of money in the bank exceed Tom’s?

I am lost how to start this function, so that I can solve this. If anyone can just start it for me, I would greatly appreciate it.

Answer 1

Okay this is what you have to do

Answer 2

you know Sue adds 30 every week

Answer 3

and she has 700

Answer 4

Tom has 900 and he loses 20 a week

Answer 5

So make a table

Answer 6

k, so I can use function equation for it?

Answer 7

yes

Answer 8

y=20x+900

Answer 9

that's where im having the brain fart

Answer 10

my bad -20x

Answer 11

y=-20x+900

Answer 12

y=30x+700

Answer 13

and then y=30x+700

Answer 14

just graph it and use slope-intercept form

Answer 15

Yes

Answer 16

You know what slope-intercept form is don't you?

Answer 17

ok, thanks a bunch.. my brain is fried and I think it was so simple I couldn't think of it. lol

Answer 18

yeah

Answer 19

haha you're welcome

Answer 20

Tell me if you need any further assistance in Algebra 1 took it last year

Answer 21

taking Geometry right now

Answer 22

I'm taking geometry this year too..I'm switching from home-school to a catholic high school for my 9th grade year. I'm just finishing up my algebra I, so I am ready for geometry in 2 weeks

Answer 23

Oh cool

Answer 24

I am going to take Algebra 2 this upcoming school year

Answer 25

Taking Geometry on FLVS

Answer 26

(Florida Virtual School)

Answer 27

yeah, cant play football in high school unless I go to an physical school

Answer 28

haha true

Answer 29

cool used to go to treca digital academy in ohio

Answer 30

Okay got to go

Answer 31

Can you give me a medal?

Answer 32

For helping you?

Answer 33

medal given

Answer 34

x = number of weeks.

You have the two equations correct:
Sue's money goes up as y = 700 + 30x
Tom's money goes down as y = 900 - 20x

Now set the equations equal and solve for x.
700 + 30x = 900 - 20x

The answer will give you the number of weeks it takes for Sue and Tom ot have the same amount of money. When you add 1 week to that, you 'll have your answer.