Question

Please help me on this thank u

Answer 1

If h=0 represents the base of the model, then ...
  The bridge touches the base of the model at 2 feet and 6 feet from the leftmost edge of the model.

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When in doubt, use your calculator to graph it.

Here, the solution is not so hard. We're looking for h(x) = 0.
Multiply by -2
  (x -4)² -4 = 0
  (x -4) = ±√4
  x = 4 ±2 = {2, 6}