The formula a = p(1 + r)^2 is used to find the amount of money, a, in an account after p dollars have been invested in the account paying an annual interest rate, r, for 6 years. find the interest rate r if $1,500 grows to $2,535 in 6 years.

The interest rate after 6 years would be 5%.

Step-by-step explanation:

The proper equation for simple interest over time is A=P(1+rt), where 'A' is the amount of money after the principal amount 'P' has been invested at an interest rate 'r' over a certain amount of time 't'.  In order to find the interest rate 'r', we need to plug in the given values of the other variables.  So, $2535=$1500(1+6r).  To solve, we need to first divide both sides of the equation by 1500 to get 1.3 = 1 + 6r, then subtract 1 from both sides to get 0.3=6r, then divide both sides again by 6 in order to get the final answer of 0.05, which when multiplied by 100 gives us a percentage of 5%.  

x=3.4   y=-5.8  (the steps are in order and I explained to the best of my ability)

Step-by-step explanation:

x+3y=-14                      substitute the x for -14-3y in the second problem

x=-14-3y                       2(-14-3y)-4y=30

                                   -28-6y-4y=30

                                   -10y=58

                                   y=-5.8

substitute the y in the first equation for -5.8

x+3(-5.8)=-14

x-17.4=-14

x=3.4