Answer: The span of the bridge is 59.77ft
Step-by-step explanation:
The standard form of equation for an ellipse with vertical major axis is:
(x-h)^2/b^2+(y-k)^2/a^2=1,a>b, (h,k)=(x,y) coordinates of center.
For given problem:
Place center of ellipse, (0,0) at center of bridge at ground level.
Given length of vertical major axis=70=2a
a=35
a^2=1225
Equation of an ellipse with horizontal major axis with center at (0,0)
Equation of ellipse:
x^2/b^2+y^2=1
plug in coordinates of given point on ellipse(27, 15)
27^2/b^2+15^2/a^2=1
729/b^2+225/1225=1
729/b^2=1-225/1225= 0.816
b^2=729/0.816≈ 893
b≈29.88
length of minor axis=2b≈59.77 ft
span of bridge≈59.77 ft