68x87 i think?
sorry if that isnt right..
The answer is -7.35x+0.09x to the power of 2
Keywords
triangle,perimeter,distance, length, side, points
we know that
The <u>perimeter</u> of a<u> triangle</u> is the sum of the three <u>length</u> <u>side</u>
To find the<u> length</u> <u>side</u> calculate the <u>distance</u> between two <u>points</u>
The formula to calculate the <u>distance</u> between to <u>points</u> is equal to

Step 1
Find the <u>distance</u> ZY
substitute the values


Step 2
Find the <u>distance</u> XY
substitute the values

Step 3
Find the <u>perimeter</u> of the <u>triangle</u>

we have


Substitute

therefore
the answer is

Answer:
The balance after four years is $1129.27
Step-by-step explanation:
The formula for compound interest, including principal sum, is 
- A = the future value of the investment/loan, including interest
- P = the principal investment amount (the initial deposit or loan amount)
- r = the annual interest rate (decimal)
- n = the number of times that interest is compounded per unit t
- t = the time the money is invested or borrowed for
∵ $800 is deposited in an account
∴ P = 800
∵ The account pays 9% annual interest
∴ r = 9% = 9 ÷ 100 = 0.09
∵ The interest is compounded annually
∴ n = 1
∵ The time is 4 years
∴ t = 4
- Substitute the values of P, r, n, and t in the formula above
∵ 
∴ 
∴ A = 1129.265
∴ The balance after four years is $1129.27