SOLUTION: 9) Solve by using quadratic formula x2 + 2x – 4 = 0

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Question 294772: 9) Solve by using quadratic formula x2 + 2x – 4 = 0
Found 2 solutions by jim_thompson5910, richwmiller:
Answer by jim_thompson5910(35256)   (Show Source): You can put this solution on YOUR website!
9)

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=2, and c=-4




Square 2 to get 4




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



Now break up the fraction



or



Simplify



or



So the solutions are:

or





==============================================

10)

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=-3, and c=-10




Negate -3 to get 3




Square -3 to get 9 (note: remember when you square -3, 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



Answer by richwmiller(17219)   (Show Source): You can put this solution on YOUR website!
Do not submit more than one problem at a time
No similar problems and
Limit of 4 problems daily (daily not at a time)
So you used up your quota for the day in one submission.
x^2 is x^2 not x2 which can be understand as 2x
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