The height of the arch is given by the quadratic equation:
y=2x−0.1x2 To find the maximum height, differentiate y with respect to x and set the derivative to zero:
dxdy=2−0.2x=0⟹x=0.22=10 Verify that this is a maximum:
dx2d2y=−0.2<0 Substitute x=10 into the original equation:
ymax=2(10)−0.1(10)2=20−0.1(100)=20−10=10 meters Thus, the maximum possible height of the arch is 10 meters.
Hence, the correct option is (B).