Answer: y = - 60 x +150
Step-by-step explanation:
Here, the function which represents the distance between my friend and restaurant,
y = - 40x +100
Where, x is the number of hours since my friend left home.
Since, when he covered the whole distance y = 0
Then -40x +100 = 0
⇒ -40x = -100
⇒ x = 2.5
Thus, he is taking 2.5 hours to covered the whole distance.
And, According to question, me and my friend take the same time to covered the distance.
Thus, the time taken by me to covered 150 miles distance = 2.5 hours.
Therefore, my speed = 150/2.5 = 60 miles per hour.
Thus, in x hour the distance between me and restaurant,
y = 150 - 60x
Which is the required equation.
