SOLUTION: I need a sample of how to solve x2+6x-16=0 I need a step by step process, as I do not understand

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Question 1061293: I need a sample of how to solve x2+6x-16=0
I need a step by step process, as I do not understand

Found 3 solutions by rfer, josgarithmetic, ikleyn:
Answer by rfer(16322)   (Show Source): You can put this solution on YOUR website!
x^2+6x-16
ax^2+bx+c
a=1
b=6
c=-16
-----------------
[-6+-(sqrt6^2-4*1*-15)]/(2*1)
[-6+-(36+60)]/2
(-6+9.8)/2
3.8/2=1.9 (0,1.9)
(-6-9.8)/2
-15.8/2=7.9 (0,7.9)
the two zeros

Answer by josgarithmetic(39617)   (Show Source): You can put this solution on YOUR website!
is factorizable.


Will 2 and 8 work? Which of these should be made negative?



------signs not right.



------Just like what we were given.





See this lesson if you find a quadratic equation that you cannot factorize the quadratic member.


Answer by ikleyn(52781)   (Show Source): You can put this solution on YOUR website!
.
I need a sample of how to solve x^2 + 6x - 16 = 0
I need a step by step process, as I do not understand
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

There is a quadratic formula to solve any quadratic equation of the form

 = .

This formula is 

 = .

It gives two solutions (two roots)  (when you use the sign "+" at the square root) and  (when you you use the sign "-" at the square root).

In your case  a= 1, b= 6 and c= -16.
Apply the formula. You will get

 =  =  =  = .

So, the two roots are:  =  =  = 2;

                        =  =  = -8.

The solutions of the given equations are 2 and -8.

Solved.


On solving quadratic equations see the lessons
    - Introduction into Quadratic Equations
    - PROOF of quadratic formula by completing the square

    - Solving quadratic equations without quadratic formula
    - Who is who in quadratic equations
    - Using quadratic equations to solve word problems
in this site.


Also, you have this free of charge online textbook in ALGEBRA-I in this site
    - ALGEBRA-I - YOUR ONLINE TEXTBOOK.

The referred lessons are the part of this textbook under the topic "Quadratic equations".



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