Find the balance in the account. $3000 principal earning 3% compounded annually, after 4 years.

2. a tractor costs $14,340 and depreciates in value by 15% per year. how much will the tractor be worth after 3 years?

Part 1)  

Part 2)

Step-by-step explanation:

Part 1) we know that    

The compound 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  in decimal

t is Number of Time Periods  

n is the number of times interest is compounded per year

in this problem we have  

substitute in the formula above  

Part 2) we know that

The formula to calculate how much will the tractor be worth after t years is equal to

where  

C is the original cost  

P is the depreciated value  

r is the rate of depreciation  in decimal

t is the number of years  

in this problem we have  

substitute the values

x = 10.1

step-by-step explanation:

all of the angles of a tirangle add up to 180º

180 - 65 = 115 (since we already know the value of one angle)

(2x + 7) + (8x + 7) = 115

(combins like terms) 10x + 14 = 115

(isolate the variable subtract 14 from both sides): 10x = 101

(find the variable divide both sides by 10): x = 101/10

x = 10.1