SOLUTION: I am struggling with this problem I need to solve it using quadratic formula. Any help would be appreciated. xē – 10x – 1 = -10

Algebra ->  Quadratic Equations and Parabolas  -> Quadratic Equations Lessons  -> Quadratic Equation Lesson -> SOLUTION: I am struggling with this problem I need to solve it using quadratic formula. Any help would be appreciated. xē – 10x – 1 = -10      Log On


   

Question 94618: I am struggling with this problem I need to solve
it using quadratic formula. Any help would be
appreciated.
xē – 10x – 1 = -10
Answer by Edwin McCravy(20054) About Me  (Show Source):
You can put this solution on YOUR website!
I am struggling with this problem I need to solve
it using quadratic formula. Any help would be
appreciated.
xē – 10x – 1 = -10 


         xē - 10x - 1 = -10

Get 0 on the right by adding 10 to both sides


           xē - 10x + 9 = 0

That COULD be done by factoring, but since you
specified "the quadratic formula":

The quadratic formula is:
                  ______ 
            -b ą Öbē-4ac
        x = —————————————
                2a 

where a = 1; b = -10; c = 9

                       ______________
             -(-10) ą Ö(-10)ē-4(1)(9)
        x = ——————————————————————————
                      2(1) 
                   ______ 
             10 ą Ö100-36
        x = ——————————————
                   2

                   __ 
             10 ą Ö64
        x = ———————————
                 2 

                   
             10 ą 8
        x = ————————
               2 


                        
Using the +, x = %2810%2B8%29%2F2 = 18%2F2 = 9
                       
Using the -, x = %2810-8%29%2F2 = 2%2F2 = 1

Those are the two solutions.

Edwin