Question

Write the point-slope form of the line that passes through (1, -5) and is perpendicular to a line with a slope of 1.

Answer 1

Two perpendicular lines have inverse reciprocal slopes.

m = - 1

y = mx + b

where:

m: slope
b: y-intercept

y = -x + b

using thg point (1,-5):

-5 =  - 1 + b 

b = -4

y = -x - 4