Using a linear function, it is found that $62.95 will be in her account after 4 weeks.
What is a linear function?
A linear function is modeled by:
y = mx + b
In which:
- m is the slope, which is the rate of change, that is, by how much y changes when x changes by 1.
- b is the y-intercept, which is the value of y when x = 0, and can also be interpreted as the initial value of the function.
For this problem, we have that:
- The initial balance is the intercept.
- The weekly deposit is the slope.
Hence, her balance after x weeks is given by the following function:
B(x) = -20.21 + 20.79x.
Her balance after 4 weeks is given by:
B(4) = -20.21 + 20.79(4) = $62.95.
Hence $62.95 will be in her account after 4 weeks.
More can be learned about linear functions at https://brainly.com/question/24808124
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