Question

PLEASE HELP!!!! WILL GIVE BRAINLIEST!!!In two or more complete sentences explain how you would set up and solve the following equation: Peter opened his account with $910 and withdrew $40 per week. Marla opened her account with $470 and withdrew $20 weekly. In how many weeks will their accounts be equal?
please give me step by step explanations if possible

Answer 1

Peter's account is 910-40x, and Marla's account is 470-2x. This is a system, so you must find the number that makes both equations end up with the same number. Basically trial and error. Here is what I did:

Let's try the number 10. 910-400=510 and 470-20=450. I need a higher number.

Let's try 13 next. 910-520=390 and 470-26=444. Now the number has to be lower.

Let's try 12. 910-480=430 and 470-24=446. Close, and a little lower.

11.5 is too low, and 11.7 is too high.  11.6 has Equation 1 at 446 and Equation 2 at 446.8. Very close!

It is somewhere around 11.6. I hope that this can give you a start in figuring it out, because I don't believe in giving the complete answer, because then you do not learn anything from it.

Answer 2

Answer:

Peter will have $910 - $40 * x on his account, where x is the number of the weeks. Marla will have $470 - $20 * x.

910 - 40 x = 470 - 20 x

910 - 470 = 40 x - 20 x

440 = 20 x

x = 440 : 20

x = 22

910 - 40 * 22 = 910 - 880 = $30

470 - 20 * 22 = 470 - 440 = $30

Answer: Their accounts will be equal in 22 weeks ( both of them will have $30 ).