3100 times 43 how much is this
2 answers:
You might be interested in
Answer: 2±√3 and 1/(2±√3)
This might seem wrong, but you'll understand when you read the explanation.
Step-by-step explanation:
For this problem, you can write 2 equations to find the two numbers. Let's establish x for the first number and y for the second number.
Equation 1:
x+y=4
This equation comes from the problem that says the 2 numbers add up to 4.
Equation 2:
x*y=1
This equation comes from the part that says multiplies to 1.
Even if the problem states that the numbers can be negative, it is tricking us. We know in order for the product of 2 numbers to be positive, it has to be +*+ or -*-. Since the added numbers have to be +4, we know we cannot use -1 and 1 as our answer. What we can do is to use substitution to solve for x and y.
x+y=4 becomes y=4-x
We can substitute this into equation 2.
x(4-x)=1
4x-x²=1
4x-x²-1=0
-x²+4x-1=0
Since this equation is not factorable, we use the quadratic equation, (<em>Please ignore the weird looking A that's in front of the ± sign. I don't know what's wrong with the system, but it's not supposed to be there)</em>
We plug our a, b, c into the equation and get x=2±√3.
Now that we know our x, we can plug it into any of the above equations.
(2±√3)(y)=1
y=1/(2±√3)
Our final 2 numbers are 2±√3 and 1/(2±√3)
After 5 years Lily has $750+$225 = $975
The equation for interest rate looks like:
750 * x^5 = 975
x^5 = 975/750
x^5 = 1.3
x =![\sqrt[5]{1.3}](https://tex.z-dn.net/?f=%20%5Csqrt%5B5%5D%7B1.3%7D%20)
x = 1,0538
That means that interest rate is approximately 5,5% (B)
The reason for this calculation is because each year you multiply your money with interest rate and add that to your starting money.
After one year you will earn
750 + 750 * interest rate = money after 1 year.
After 5 years we multiply 5 times so our interest rate is x^5 and money after 5 years is 750 + 225.
The equation for interest rate looks like:
750 * x^5 = 975
x^5 = 975/750
x^5 = 1.3
x =
x = 1,0538
That means that interest rate is approximately 5,5% (B)
The reason for this calculation is because each year you multiply your money with interest rate and add that to your starting money.
After one year you will earn
750 + 750 * interest rate = money after 1 year.
After 5 years we multiply 5 times so our interest rate is x^5 and money after 5 years is 750 + 225.