To effectively determine the correct answer, it would be helpful to write this into an algebraic expression. We let x as the number. We do as follows:
<span>Four times the square of a certain number increased by 6 times the number equals 108.
4x^2 + 6x = 108
The numbers can be either of the following since the equation generated was a quadratic equation which has two roots.
x = 4.5
x = -6 </span>
12 dollars is discounted off, making the price 28 dollars.
Step-by-step explanation:
10 percent is 4$, 4×3=12
Answer:
In 2012 , the population will be 15 million
Step-by-step explanation:
We start by setting up an exponential equation that defines the increase
P(t) = I(1 + r)^t
P(t) represents the present population = 15 million
I is the population in 2007 which is 13.8 million
r is 1.6% = 0.016
t is what we want to calculate
15 million = 13.8 million (1 + 0.016)^t
15/13.8 = (1.016)^t
1.09 = (1.016)^t
ln 1.09 = t ln 1.016
t = ln 1.09/ln 1.016
t = 5.429 which is approximately 5
So in 2007 + 5 = 2012, the population will be 15 million
