eight less than the square ofa number is twice the number

Question

8-2x=2

 

 

Answer 1

Hi Johana...I'll take a crack at this one the way I read it.

 

 

              X^2  -8  =2x           Now rewrite.....Its a quadradic...

 

              X^2  -2x  -8   =0     Now factor.....

 

           (X  -4)      (x+2)

 

             X=4    or   X=-2

 

 

        Now substitute into   X^2 -8  =  2x

 

                                          (4)^2   -8   =2(4)

                                              16   -8     =8

                                                   8      =8   ---->  checks

 

     X^2-8 =2x

 

    (-2)^2  -8   =  2(-2)

 

          4     -8     =   -4

 

              -4      =   -4   ------->  checks                   

 

 

         Hope this helps!