Help w/ Calculus Problem: Kaplan Review #2

[Futbol99]

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I am doing the review problems in my 2013-2014 Kaplan Pre-Calculus and Calculus Chapter and I am stuck on #2, and I kind of feel there is a mistake in the question, so I need some insight please!

Question:
Line A is perpendicular to the line with equation y= -1/3X and the point is on line A. Which of the following is the equation of line A?
A) y= -1/3X + 4
B) y= 1/3x
C) y= 3x
D) y= 3x - 22

I originally thought the answer was C, but it was not. I have such a hard time trying to understand the solution for the second part of the problem. I understand how to get the slope but I didn't get the next part of the answer. (The Answer is D). The solution is saying "We also already know that line A goes through the point (6,-4). This part is REALLY frustrating me because I do not know where they pulled that number from and where it is coming from! I tried working backwards from the answer and I feel there was a mistake in this question. I'm a little rusty with math, so maybe it just went over my head.

Thanks for your time.

 

[nxq875]

Assuming the question actually provided you with the coordinates (6, -4).
It's the point/slope equation:
Y - y1 = m(x-x1)
plug in the coordinates and slope
Y - (-4) = 3(x-6)
simplify: y + 4 = 3x - 18
y = 3x - 22
(D)

 

[Futbol99]

Assuming the question actually provided you with the coordinates (6, -4).
It's the point/slope equation:
Y - y1 = m(x-x1)
plug in the coordinates and slope
Y - (-4) = 3(x-6)
simplify: y + 4 = 3x - 18
y = 3x - 22
(D)

I know how to get the answer if the coordinates are given 😛
Im just wondering, ARE they given from that question? It was not given to me, so I had no way of knowing to get (6,-4). So I was asking if this was an error in the question or am I missing something from the question to interpret that as I dont know where that coordinate came from.

 

[nxq875]

I don't have the Kaplan book so I wouldn't know....but from the looks of the question, was there a graph provided?

 

[Futbol99]

I don't have the Kaplan book so I wouldn't know....but from the looks of the question, was there a graph provided?

Nope. What I wrote is exactly what was provided.

 

[nxq875]

Maybe the publisher was a lil drunk and forgot to give a graph lol, because idk where that point came from either

 

[jkral1102]

I'm currently reading this book myself for the Sep 5 PCAT and I've noticed tons of errors in this book. This question is definitely an error too since there's know way you could know b in y=mx+b if there were no coordinates provided in the question
I wouldn't rely solely on just the Kaplan book for prep. I've got a Dr Collins hard copy coming in the mail and I'm also reviewing all my gen chem/ochem/calc/algebra/anatomy/physiology/biochem notes from old classes. Good luck

 

[Futbol99]

I'm currently reading this book myself for the Sep 5 PCAT and I've noticed tons of errors in this book. This question is definitely an error too since there's know way you could know b in y=mx+b if there were no coordinates provided in the question
I wouldn't rely solely on just the Kaplan book for prep. I've got a Dr Collins hard copy coming in the mail and I'm also reviewing all my gen chem/ochem/calc/algebra/anatomy/physiology/biochem notes from old classes. Good luck

Same here man, i have Dr. Collins too that im using. The only problem is I find the "Content" on there reallllly light. Good thing I can still recall a ton of stuff to make me still use it but Kaplan sometimes covers things not in Collins and vice versa so Im just complementing them. I spent a good 15 mins just staring at the question, trying to give them the benefit of the doubt -_-. Good to know it has errors and I'm worried about missing other errors...