M∠ABC=180°
7x+x-4 = 180
8x = 180+4
8x=184
x=184:8
x=23
∠DBС = x-4 = 23-4 = 19°
Answer: 19°.
9514 1404 393
Answer:
14.1 years
Step-by-step explanation:
Use the compound interest formula and solve for t. Logarithms are involved.
A = P(1 +r/n)^(nt)
amount when P is invested for t years at annual rate r compounded n times per year.
Using the given values, we have ...
13060 = 8800(1 +0.028/365)^(365t)
13060/8800 = (1 +0.028/365)^(365t) . . . . divide by P=8800
Now we take logarithms to make this a linear equation.
log(13060/8800) = (365t)log(1 +0.028/365)
Dividing by the coefficient of t gives us ...
t = log(13060/8800)/(365·log(1 +0.028/365)) ≈ 0.171461/0.0121598
t ≈ 14.1
It would take about 14.1 years for the value to reach $13,060.
<span>Lets make it clear: You would have a positive answer when the value you are looking for has to be a positive number. On the other hand you would have a positive and a negative answer when you take the square root of something that doesn't have to be positive. it could be either because when a negative number is squared it becomes positive and when a positive number is squared it stays positive as well.</span>
