Answer:
A. f(x)=x^2+x+0.25
Explanation:
If x represents Lindsey's distance at 2:00 PM, then 2x represents Kara's distance at 2:00 PM because she walked twice as far as Lindsey. Then adding on the values we got for 2:30 PM, we get that Kara walked a distance of 2x+1 and Lindsey walked a distance of x+0.5 at the time of 2:30 PM. Now, we know that they have formed a right triangle because we are given the directions they walked in; east and north. This allows us to use a formula for the area of a right triangle: 1/2(L x W). Plugging in our values, we get...
1/2(2x+1)(x+0.5)
which simplifies to...
1/2(2x^2+2x+0.5)
which further simplifies to...
x^2+x+0.25
which is our answer.