SOLUTION: d² + 3d - 7 = 0

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Question 88145: d² + 3d - 7 = 0
Answer by Edwin McCravy(20054) About Me  (Show Source):
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           d² + 3d - 7 = 0

Use the quadratic formula, which gives 
the solution to

          ax² + bx + c = 0

The quadratic formula is
                  ______ 
            -b ± Öb²-4ac
        x = —————————————
                2a 

Compare 

           d² + 3d - 7 = 0
to

          ax² + bx + c = 0

we see that:  a = 1; x = d; b = 3; c = -7

                     _____________
             -(3) ± Ö(3)²-4(1)(-7)
        d = ————————————————————————
                     2(1) 
                   ____ 
             -3 ± Ö9+28
        d = —————————————
                  2

                   __ 
             -3 ± Ö37
        d = ———————————
                 2 

                      
Edwin