Li deposited $17,500 into a bank account that earned simple interest each year. after 2 years, he had earned $2975 in interest.

if no money was deposited into or withdrawn from the account, what was the annual interest rate?

R = 8.5%/year

Equation:
r = (1/t)(A/P - 1)
Calculation:
Solving our equation
r = (1/2)((20475/17500) - 1) = 0.085
r = 0.085
converting r decimal to a percentage
R = 0.085 * 100 = 8.5%/year

The interest rate required to get
a total amount, principal plus interest, of $ 20,475.00
from simple interest on a principal of $ 17,500.00
over 2 years is 8.5% per year.

3x+9+4x+x=8x+9that's the answer for your question.