<span>arctan(2x) = -1 radian
</span>⇒ 2x = tan(-1)
⇒ 2x = -1.5574
⇒ x = -1.5574/2
⇒ x = - 0.7787<span>
</span>
First you would have to find the third angle in the triangle which you would do by adding 63+61 and subtracting the resulting number from the total degrees in a triangle. From there, you would calculate x and y using the knowledge that angles on a line equal 180.
Answer:
$ 50,340.97
Step-by-step explanation:
From the above question, we can deduce that we are to find the Initial amount invested which is also called the Principal.
The formula to find Principal in a compound interest question is:
P = A / (1 + r/n)^nt
Where:
A = Total Amount obtained after invested = $80,000
r = Interest rate = 3.1% = 0.031
n = number of times interest in compounded = Quarterly = 4
t = time in years = 15
P = $80,000/(1 + 0.031/4)^4 × 15
P = $80,000/(1 +0.00775)^60
P = $ 50,340.97
Hence, James would have to invest $50,340.97 today to have $80,000 in 15 years.
+ 2 x 
+ 7 x 
