Question

David opens a bank account with $140 and then deposits $150 each month. Louis opens a bank account with $260 and deposits $120 each month.

How many months will it take for David and Louis to have equal amounts of money in their accounts?

A.
2

B.
4

C.
5

D.
7

Answer 1

plz help Medal to best answer and Fan

Answer 2

@Michele_Laino plz help

Answer 3

you have two linear equations

Answer 4

the rate of the first account is 150 per month, and it starts at 140
y = 150*x + 140

the rate of the second account is 120 per month and starts at 260
y = 120*x + 260

Now where do these two lines intersect

Answer 5

we can mathematize both bank accounts, with a linear function, as @perl well said

Answer 6

120+260=380

Answer 7

please you have to solve the system of the two equations that @perl wrote above

Answer 8

i don't get

Answer 9

i don't get it

Answer 10

first equation:
\[y=140+150x\]

Answer 11

second equation:
\[y=260+120x\]

Answer 12

290

Answer 13

please you have to find x such that both bank accounts are equal,
so:
\[260+120x=140+150x\]
please, solve for x

Answer 14

i am going to do a different test i don't get anything you are telling me so sorry

Answer 15

i guessed and got 80% and passed i said it was B

Answer 16

I solve the equation above!

Answer 17

we have:
\[30x=120\]
from which:
\[x=4\]
so after 4 months david and Louis have the same quantity of money

Answer 18

x is number of months
y is the money quantity,
so after 4 months, both David and Louis have
740$

Answer 19

since 150*4+140=740, and
120*4+260=740

Answer 20

is it all clear, please? @TeenWolfGirl

Answer 21

so B.

Answer 22

yes thank you

Answer 23

thank you! @TeenWolfGirl