Answer:
The annual interest rate is 12.05%.
Step-by-step explanation:
The simple interest is given by the formula:
Where I denotes interest.
P denotes the principal amount.
R denotes the rate of interest
and T denotes the time period.
I=$160.67, P=$2000, t=8 months=8/12 years (Since 12 months=1 year so 1 month=1/12 year)
Hence, the annual interest rate is 12.05%.
the parabola has maximum at 9, meaning is a vertical parabola and it opens downwards.
it has a symmetry at x = -5, namely its vertex's x-coordinate is -5.
check the picture below.
so then, we can pretty much tell its vertex is at (-5 , 9), and we also know it passes through (-7, 1)
Given:
Rate of simple interest = 5%
Time = 4 years
Total interest = $160
To find:
The amount borrowed by Austin from a credit union.
Solution:
The formula for simple interest is:
Where, P is principal, r is the rate of interest and t is the number of years.
Putting in the above formula, we get
Multiply both sides by 5.
Therefore, Austin borrowed $800 from a credit union for 4 years.