Chapter 4.1, Problem 47HP

To determine

Either of J and T are solving correct.

Answer to Problem 47HP

J’s equation is correct.

Explanation of Solution

Given information:

Two points are given as $\left(3,-2\right)$ and $\left(3,-2\right)$ .

Calculation:

Now, formula to evaluate slope of a line joining two points $\left(x_1,y_1\right)$ and $\left(x_2,y_2\right)$ is

  $Slop(m)=\frac{y_2-y_1}{x_2-x_1}$

Here,

  $\left(x_2,y_2\right)=\left(6,4\right)\text{and}\left(x_1,y_1\right)=\left(3,-2\right)$

Therefore,

  $\begin{array}{c}Slope=\frac{4-(-2)}{6-3}\\ =\frac{6}{3}\\ m=2\end{array}$

So, equation of line joining these two points will be

  $\begin{array}{l}y-y_1=\frac{y_2-y_1}{x_2-x_1}\left(x-x_1\right)\\ y+2=2(x-3)\\ y+2=2x-6\\ y=2x-8\end{array}$

So, J’s equation is correct.