Question

17. Write an equation in slope-intercept form for the line perpendicular to y = 3x - 9 that passes through the point (9,-9). Explain how you got your answer.

Answer 1

y=-1/3x-6

Explanation:

Perpendicular lines have slopes that are negative and reciprocal; if you multiply them together, the result is -1

so, to find the slope of the new line:

3m=-1

divide by 3

m=-1/3

the slope of the new line is -1/3

Slope-intercept form is written as y=mx+b, where m is the slope and b is the y intercept.

Here's our equation so far:

y=-1/3x+b

since the line passes through the point (9,-9), we can use it to solve for b

substitute into the equation:

-9=-1/3(9)+b

-9=-3+b

-6=b

b is -6

here's our equation

y=-1/3x-6

hope this helps! :D