We have that
2sin²<span>x - sinx - 3 = 0
</span>
Let
A------> sin x
so
2A²-A-3=0
using a graph tool-----> to resolve the second order equation
see the attached figure
the solutions are
A=-1
A=1.5------> is not solution because sin x <span>can not be 1.5
the solution is
A=-1
therefore
sin x=-1
x=arc sin(-1)=-90</span>°
the answer is
sin x=-1x=-90° or 270°
The person would have to leave the money in the bank for 7.8 years for it to reach 13,500 dollars.
Step-by-step explanation:
Step 1; First we must calculate how much interest is generated for a single year. The annual interest rate is 4.5% i.e. 4.5% of 10,000 dollars which equals 0.045 × 10,000 = 450 dollars a year. As the years pass, more and more will be put into the account due to interest.
Step 2; For there to be 13,500 dollars in the bank account we need to calculate how much money is added due to interest.
The money needed to be added through interest = 13,500 - 10,000 = 3,500 dollars.
So we need to determine how long it will take for the bank to add 3,500 dollars by adding 450 dollars a year.
The number of years to reach 13,500 dollars =
= 7.777 years. By rounding this value to the nearest tenth, we get 7.8 years.
i am certain that this is the answer
The easy thing to do is eliminate x by subtraction
x + 7y = 24
- x - 9y = -24
-------------------
16y = 48
now solve for y and then substitute the value into either original equation to find x
16/3 is rational simply because it is a fraction made up of whole numbers.
Irrational numbers cannot be expressed as fractions made up of whole numbers.