Online Course Discussion Forum

Hello I have question on II-A 3.18

 
 
YangBober的头像
Hello I have question on II-A 3.18
YangBober - 2020年10月4日 Sunday 19:13
 

Hello, In 3.18 It did not give me the x-value of point B so do I write the y-value in terms of the x-value,

But again it's the quick response isn't its answer suppose to simple?

 
ProfessorAreteem的头像
Re: Hello I have question on II-A 3.18
ProfessorAreteem - 2020年10月5日 Monday 18:58
 

With the given information you can find both the $x$ and the $y$ values of the coordinates of point $B$.

Recall in example 3.2 it was proven that the equation of the line going through points $A = (x_A, y_A)$ and $B = (x_B, y_B)$ is given by $$\dfrac{x-x_A}{x_A-x_B}= \dfrac{y - y_A}{y_A-y_B}.$$

ChenAlvin的头像
Re: Hello I have question on II-A 3.18
ChenAlvin - 2020年10月6日 Tuesday 06:52
 

Dear teacher,

I also have a question on 3.18

I got point B=(6, 18), I think it is also a correct answer, can you check if I'm right? Thanks!

ProfessorAreteem的头像
Re: Hello I have question on II-A 3.18
ProfessorAreteem - 2020年10月6日 Tuesday 14:16
 

That is correct, there are in fact a lot of solutions.