Yahoo Answers is shutting down on May 4th, 2021 (Eastern Time) and beginning April 20th, 2021 (Eastern Time) the Yahoo Answers website will be in read-only mode. There will be no changes to other Yahoo properties or services, or your Yahoo account. You can find more information about the Yahoo Answers shutdown and how to download your data on this help page.
Trending News
Math homework help? :(?
The graph of f(x) = –0.01x2 + x can be used to model the height in feet of a curved arch support for a bridge, where the x-axis represents the water level and x represents the distance in feet from where the arch support enters the water. Find the height of the highest point of the bridge.
2 Answers
- ?Lv 74 years agoFavorite Answer
f(x) = –0.01x² + x
As the coefficient on the x² term is negative, this is a parabola that opens down.
Therefor the vertex is a maximum.
From the quadratic formula the x coordinate of the vertex is
x = -b/2a
x = -1/(2 * -.01)
x = -1/(-.02)
x = 50
---------------
At x = 50
f(50) = -0.01(50)² + 50
f(50) = -25 + 50
f(50) = 25
The highest point is 25 feet <––––––
- DWReadLv 74 years ago
² can be represented by ^2.
f(x) = -0.01x² + x
= -0.01(x² - 100x)
= -0.01(x² - 100x + 50²) + 0.01·50²
= -0.01(x - 50)² + 25
This is the equation for a down-opening parabola with vertex (50,25). The highest point of the bridge is 25 ft.