Answer:
x=3
Step-by-step explanation:
We are given the equation

This can be rewritten as

Now using the quotient rule for logarithms we can combine these two

Next we can remove the log by using an inverse operation

Now we can solve for x

Answer:
x = - 7
Step-by-step explanation:
- 3x + 7 = 28
- 3x + 7 - 7 = 28 - 7
- 3x = 21
- 3x/3 = 21/3
- x = 7
x = - 7
Answer:
y = 5 e^r * t
Let y be the population in billions and t the value of elapsed years
7 = 5 e^r * t is the equation being used where t = 15
7/5 = e^r * t
ln 7/5 = r * t taking ln of both sides
r = .336 / 15 = .0224
y = 5 e^(.0224 t) is then our equation
Check - suppose you want y at 2020
y = 5 e^(.0224 * 20) would be the equation
y = 5 e^.449 = 7.83 billion - seems to be a reasonable answer
Always remember that percent means "out of 100". That means the 40%=40/100=.4
so 40% of 120 is equivalent to .4(120)=48
Hope I helped