A bank has a saving rate of 6% simple interest per year if a customer deposit $4000 in a new account and does not add or withdrawn any money to the account how much simple interest will the customer make in 4 months

the interest rate is .68% per year

Step-by-step explanation:

You deposit $4000 into a bank account and received $9 simple interest after 4 months. The interest rate was 0.68% per year.

Explanation:

STEP 1: Convert 4 months into years.

STEP 2: Find interest rate by using the formula , where I is interest, P is total principal, i is rate of interest per year, and t is total time in years.                    $9, P = $4000 and t = 0.3333 years, so

x = -3

y = -18

step-by-step explanation:

to solve by substitution, substitute one variable and solve for the other. then substitute again to find the remaining variable.

x-1/3(3x-9) = -3 since y=3x-9 substittute y.

x-1/3(3x-9)=-3

x + x +3 = -3

2x+3=-3

2x+3-3= -3-3

2x=-6

x=-3

substitute again into y=3x-9

y=3(-3)-9

y=-9-9

y=-18