Y=ax+b, y=cx+d (a≠0, c≠0)
If the two line cross perpendicularly ⇔ ac= -1
So a tangent of the perpendicular line is "-(1/5)".
Then, the equation of the perpendicular line is y=-(1/5)x+a (a is <span> y-intercept</span>).
On the other hand, this equation pass r(1, 3), so
3 = -(1/5) times 1 + a
∴ a=16 / 5
Therefore, y=-(1/5)x+16 /5 is answer.
By the way, I'm Japanese so if you find some mistakes in my English, please let me know.
On the first day, they traveled for 10 hours with an average speed of 60 mph. Which means on the first day they traveled 600 miles.
Since the total distance is 1023 miles and presumably they will be going at a speed of 60 mph. We divide the miles by the rate:
1023/60 = 17.05
So it will take 17.05 hours to drive the whole way to Florida.
The answer to this question is D.
