Mason download an app for four dollars. The app has a monthly fee of three dollars per month. Tatum download the same app that cost $20 and has monthly fees of one dollar per month how many months before Mason and Tatum had paid the same amount?

Step-by-step explanation:

step 1. let Mason = m and Tatum = t

step 2. m = 3x + 4 ($3/month and one time $4)

step 3. t = 1x + 20 ($1/month and one time $20)

step 4. 3x + 4 = x + 20 (set equations equal)

step 5. 2x = 16 (collect like terms)

step 6. x= 8 ( 8 months)

I went ahead and rewrote x+6y=61 to x=-6y+61 to get x by itself.

I then plugged that into to the first equation to get:

4(-6y+61)-5y=-17

I factored to get:

-24y+244-5y=-17

I combined like terms

-29y=-261

I then divided both sides by -29 to get y by itself and I got y=9 which is A.