Sally chooses Plan 1 to set aside $1.00 each day for savings. Kyle decides to use Plan 2. On each consecutive day, he will
double the amount of money in his savings from the previous day. The table shows the amount of money that each person
saved on the first 10 days. Which plan represents an exponential function? Justify your answer.

Depends on whether you wish for it to change/alter or be constant +1b +1b for day 2 or 1b +1. Each work. The exponential function is better for small numbers that start with totals. It can also be a function to multiply days to work and count faster for Sally.

Step-by-step explanation:

The coefficient “a” is. called the initial value of the function (or the y-intercept), and “f(x)” represent the dependent variable (or output of the function)

With this in mind there are 4 value inputs to create each daily change.

a = y kyles x2 value) (f)x = Kyles money  and for Sally b1 and b.

Therefore for Sally staying $1 a day we can use the constant a=y and match this to b) where b= 1 + y=1 and a^2 = 2 (you could also use y^2). This way y can mean $0.50 when y^2  is used incorrectly for Sally when it should be used for Kyle. Within all calculation. if b=1  then it is used for matching day 2,3,4,5 etc as we would have day 2 $2 = 1b +b then 2b +b etc.  

{x = -1/2 ,   y = -1

step-by-step explanation:

solve the following system:

{2 x + y = -2

{10 x - 3 y = -2

in the first equation, look to solve for y:

{2 x + y = -2

{10 x - 3 y = -2

subtract 2 x from both sides:

{y = -2 x - 2

{10 x - 3 y = -2

substitute y = -2 x - 2 into the second equation:

{y = -2 x - 2

{10 x - 3 (-2 x - 2) = -2

10 x - 3 (-2 x - 2) = (6 x + 6) + 10 x = 16 x + 6:

{y = -2 x - 2

{16 x + 6 = -2

in the second equation, look to solve for x:

{y = -2 x - 2

{16 x + 6 = -2

subtract 6 from both sides:

{y = -2 x - 2

{16 x = -8

divide both sides by 16:

{y = -2 x - 2

{x = -1/2

substitute x = -1/2 into the first equation:

{y = -1

{x = -1/2

collect results in alphabetical order:

answer:   {x = -1/2 ,   y = -1