Question

Jevonne is on his way home from a vacation. He is staring 818 miles from home and drives about 65 miles per hour. The function d=818-65,h represents Jevonne distance from home d after driving h hours.

part c: Examine the graph of the function to estimate to the nearest tenth how many hours it takes jevonne to get home.​

Answer 1

12.6 hours

Explanation:

Let's rewrite the function in proper notation. "d=818-65,h" is better expressed as:

d = (818 miles) - (65 m/hr)*h, where d is distance in miles and h is time in hours. -(65 m/hr)*h is the distance subtracted form 818 miles for time h (ih hours).

Home is at distance 0 miles. The problem is asking for the time it will take, h, in hours, to reduce 818 miles to 0 miles, Home.

We'll use y in place of h and x in place of h to get the more familiar:

y = -65x + 818

A graph of y = -65x + 818 is attached.

The line intersects the x axis at 12.6: point (12.6,0).

This means that Jevonne takes 12.6 hours to reach home driving at 65 miles/hr from his vacation spot 818 miles away from home.

If we find the answer, h, by solving the equation, instead of graphing, we get a more precise answer of 12.584615 . . .. Graphing is less precise, but sufficient for this problem " . . .the nearest tenth").