Question 107173: i need some help with these i am trying to solve these by quadratic equation formula and these are the answer that i came up with.
(x - 1)^2 = 7
i am getting 1 +- sqrt 7
x^2 - 9x - 4 = 6
i get -1 and a 10
4x^2 - 8x + 3 = 5
i am getting 2 +-sqrt 6/2
Answer by MathLover1(20849) (Show Source):
You can put this solution on YOUR website! 



Check:
(3.64 – 1)^2 = 7
2.64)^2 = 7
x^2 - 9x - 4 = 6 …move to the left
x^2 – 9x – 4 – 6 = 0
x^2 – 9x – 10 = 0
Solved by pluggable solver: Quadratic Formula |
Let's use the quadratic formula to solve for x:
Starting with the general quadratic

the general solution using the quadratic equation is:

So lets solve ( notice , , and )
Plug in a=1, b=-9, and c=-10
Negate -9 to get 9
Square -9 to get 81 (note: remember when you square -9, you must square the negative as well. This is because .)
Multiply to get 
Combine like terms in the radicand (everything under the square root)
Simplify the square root (note: If you need help with simplifying the square root, check out this solver)
Multiply 2 and 1 to get 2
So now the expression breaks down into two parts
or 
Lets look at the first part:

Add the terms in the numerator
Divide
So one answer is

Now lets look at the second part:

Subtract the terms in the numerator
Divide
So another answer is

So our solutions are:
or 
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… move to the left

Solved by pluggable solver: Quadratic Formula |
Let's use the quadratic formula to solve for x:
Starting with the general quadratic

the general solution using the quadratic equation is:

So lets solve ( notice , , and )
Plug in a=4, b=-8, and c=-2
Negate -8 to get 8
Square -8 to get 64 (note: remember when you square -8, you must square the negative as well. This is because .)
Multiply to get 
Combine like terms in the radicand (everything under the square root)
Simplify the square root (note: If you need help with simplifying the square root, check out this solver)
Multiply 2 and 4 to get 8
So now the expression breaks down into two parts
or 
Now break up the fraction
or 
Simplify
or 
So the solutions are:
or 
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