Question

At the beginning of the year, John had $40 in savings and saved an additional

$13 each week thereafter. Isaac started the year with $80 and saved $9 every
week. Let J represent the amount of money John has saved t weeks after the
beginning of the year and let I represent the amount of money Isaac has
saved t weeks after the beginning of the year. Write an equation for each
situation, in terms of t, and determine the number of weeks after the
beginning of the year until John and Isaac have the same amount of money
saved.

Answer 1

J= 40+13t

I= 80+9t

they are equal at 10 weeks

Explanation:

So we can start this by writing our equations

J= 40+13t

I=80+9t

To figure out when they're equal set the two equations equal to each other and solve for t

40+13t=80+9t

subtract 40 and 9t from both sides to get

40=4t

divide by 4 and get

t=10