Answer:
[tex]at \: x - intercept, \: ax) = 0 \\ (x - 4)(x + 4) = 0 \\ {x}^{2} = 16 \\ x = {}^{ + } 4 \: \: and \: \: {}^{ - } 4 \\ = > ( {}^{ + } 4, \: 0) \: and \: ( {}^{ - } 4, \: 0) \\ midpoint = ( \frac{4 - 4}{2} , \: \frac{0 + 0}{2} ) \\ midpoint = (0, \: 0)[/tex]