Answer:
The interest rate was of 0.1173 = 11.73%.
Step-by-step explanation:
This is a simple interest problem.
The simple interest formula is given by:
In which E is the amount of interest earned, P is the principal(the initial amount of money), I is the interest rate(yearly, as a decimal) and t is the time.
After t years, the total amount of money is:
In this problem, we have that:
So
So
The interest rate was of 0.1173 = 11.73%.
From the linear function formed by the points given in the table, it is found that the x-intercept is of -14.
<h3>What is a linear function?</h3>A linear function is modeled by:
y = mx + b
In which:
In this problem, when x increases by 20, y decays by 6, hence the slope is given by:
Then:
y = -0.3x + b.
When x = -54, y = 12, hence:
y = -0.3x + b
12 = -0.3(-54) + b.
b = -4.2.
Thus, the equation is:
y = -0.3x - 4.2.
The x-intercept is the value of x when y = 0, hence:
-0.3x - 4.2 = 0.
x = -4.2/0.3
x = -14
More can be learned about linear functions at brainly.com/question/24808124