Answer:
Quadratic Formula
so
x = -5
and
x = 0.5
Step-by-step explanation:
Whenever you see a problem in this form, which you will see a lot of, you can try to factor it or use the "least squares" method or what have you, but those won't always work, unfortunately.
Fortunately, the quadratic formula will never fail you with quadratic expressions.
This is the Quadratic Formula

a is the the number on the variable with the exponent ^2
b is the number on the variable with no exponent
c is the third number
a and b cannot be equal to 0; c can be
Since we're looking for a number with an equation that has a square root in it, we're going to get two answers. These two answers come from the radical being separately added AND subtracted from the radical. It's basically two problems.
Plugging in our numbers to this equation gives us x values of -5 and 0.5. This will always work with polynomials with factors of ^2 in them.
If you have a TI-84 calculator or newer, there's a tool on it that will factor polynomials like this one for you just by giving it the numbers.
Pi. I don't know what the square root is doing there because it has no number under it.
Let the youngest sister be n years
Lana will be 2n years, as her youngest sister is half her age
The age of the twins separately will be 2n-2 as they are 2 years younger than Lana
So, the equation looks like this:
n + 2n + 2(2n-2) = 45
Now solve for n:
3n + 4n - 4 = 45
7n - 4 = 45
7n = 49
n = 7
So the youngest sister is 7, Lana is 14 and the twins are 12. 14 + 12 + 12 + 7 =45
Answer:
96
Step-by-step explanation:
once you fill in the Blanks that are solvable, you will work your way into the answer. For example, the first column, the missing number has to be 155-76 or 79. Now you can find your answer. In the second row, “no Laptop”, you have 79 (solved above) plus 17. So your answer is 79+17 or 96.