To find the slope of a line, you take two points on the line, then use their X and Y coordinates in the following formula:
slope = ( Y2 -Y1 ) / ( X2 - X1)
By simplifying the answer, you will get your slope.
The line perpendicular to a line with a slope of 1/5 has a slope of -5.
The slope of a line is undefined if the line is vertical.
The slope of a line is typically expressed as a single value, and it seems there might be a misunderstanding with the notation "-1 3." If the slope of the line is -1, the slope of a line perpendicular to it is the negative reciprocal. Thus, the slope of a perpendicular line would be 1.
The slope of a line perpendicular to one with slope m is -1/m. So for a line with slope 1/7, any line perpendicular to it will have: slope = -1 / (1/7) = -7
A vertical line has a slope of infinity.
IND Concourse Line was created in 1933.
IND Crosstown Line was created in 1933.
IND Rockaway Line was created in 1956.
IND Culver Line was created in 1919.
IND Fulton Street Line was created in 1936.
IND Queens Boulevard Line was created in 1933.
Avenue I - IND Culver Line - was created in 1919.
IND Eighth Avenue Line was created in 1932.
Avenue P - IND Culver Line - was created in 1919.
Avenue N - IND Culver Line - was created in 1919.
Church Avenue - IND Culver Line - was created in 1933.
Avenue X - IND Culver Line - was created in 1919.