Question

8. Write an equation of the line perpendicular to y = x + 4 that contains (3,-3). Please write the

equation in point-slope form.

Answer 1

y + 3 = - (x - 3)

Explanation:

the equation of a line in slope- intercept form is

y = mx + c ( m is the slope and c the y- intercept )

y = x + 4 ← is in slope- intercept form

with slope m = 1

given a line with slope m then the slope of a line perpendicular to it is

`m_(perpendicular)` = -
`(1)/(m)` = -
`(1)/(1)` = - 1

the equation of a line in point- slope form is

y - b = m(x - a)

where m is the slope and (a, b ) a point on the line

here m = - 1 and (a, b ) = (3, - 3 ) , then

y - (- 3) = - 1 (x - 3) , that is

y + 3 = - (x - 3)