Line AB and BC for a right angle at point B. If A(-3,4) and B(4,4) what is the equation of line BC?

The correct answer is:

x=4.

Explanation:

The slope of line AB is given by the formula
[tex]m=\frac{y_2-y_1}{x_2-x_1}[/tex]

Using the coordinates of A and B, we have
[tex]m=\frac{4-4}{4--3}=\frac{0}{7}=0[/tex]

Perpendicular lines have slopes that are negative reciprocals. Since the slope of AB is 0/7, the reciprocal is 7/0, which is undefined.

Any line with an undefined slope is a vertical line. This will be a vertical line that passes through point B.

Vertical lines have the equation x=c, where c is a constant; since it runs through B, which has coordinates (4, 4), this means the equation is x=4.