SOLUTION: Find the solutions to the equation: x2 + 2x – 8 = 0. a. x = –4, 2 b. x = –3, 5 c. x = –2, 4 d. x = 4, 4

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Question 107670: Find the solutions to the equation: x2 + 2x – 8 = 0.
a. x = –4, 2
b. x = –3, 5
c. x = –2, 4
d. x = 4, 4

Found 2 solutions by jim_thompson5910, MathLover1:
Answer by jim_thompson5910(35256)   (Show Source): You can put this solution on YOUR website!
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=-8




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


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





So the answer is A)

Answer by MathLover1(20850)   (Show Source): You can put this solution on YOUR website!
Find the solutions to the equation:

a. = (, )
b. = (, )
c. = (, )
d. = (, )
use quadratic formula:

In the standard form

the roots are:

since you have: , , and
then:












answer is

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