Answer:
Step-by-step explanation:
we know that
The simple interest formula is equal to
where
A is the Final Investment Value
P is the Principal amount of money to be invested
r is the rate of interest
t is Number of Time Periods
step 1
Find the rate of interest
in this problem we have
substitute in the formula above and solve for r
The rate of interest is 
step 2
Find the sum of money that will amount to 25,500 in 5 years, at the same rate of interest
in this part we have
substitute in the formula above and solve for P
Answer:
(-4, 5)
Step-by-step explanation (work shown in attached picture):
1) Since x is already isolated in the first equation, substitute that value for x into the other equation to find y. So, substitute 16-4y for the x in 3x + 4y = 8, then solve for y. This gives us y = 5.
2) Now, substitute that given value for y back into any one of the equations to find x. I chose to do it in the first equation. Substitute 5 for the y in x = 16-4y, then solve for x this time. This gives us x = -4.
Since x = -4 and y = 5, the solution is (-4, 5).
Two squares root. Because 3 * 3 = 9 and -3 * -3 = 9.