SOLUTION: You can model an arch at your school using the equation y=−34(x+4)(x−4), where x and y are measured in feet. The x-axis represents the ground. Find the width of the arc

Algebra ->  Polynomials-and-rational-expressions -> SOLUTION: You can model an arch at your school using the equation y=−34(x+4)(x−4), where x and y are measured in feet. The x-axis represents the ground. Find the width of the arc      Log On


   

Question 1112390: You can model an arch at your school using the equation y=−34(x+4)(x−4), where x and y are measured in feet. The x-axis represents the ground. Find the width of the arch at ground level.

Answer by ikleyn(52874) About Me  (Show Source):
You can put this solution on YOUR website!
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The points of the arc at the ground level are located where y = 0.


In other words, these points are the roots of the equation


%28-3%2F4%29%2A%28x%2B4%29%2A%28x-4%29 = 0.


The factor  -3%2F4 is irrelevant to this consideration, and the roots are  x = -4  and  x = 4.


Thus the width of the arc at the ground level is this difference  4 - (-4) = 4 + 4 = 8 feet.

Solved.