👉 Equations of a Straight Line in Different Forms
Equations of a Straight Line
🔹 Equation of x-axis is y = 0 and that of y-axis is x = 0
🔹 Equation of a line parallel to x-axis is y = b where b is the distance of the line from the x-axis.
🔹 Equation of a line perpendicular to y-axis is x = a where a is the distance of the line from the y-axis.
Equations of a Straight Line
🔹 Equation of a line whose slope is m and which cuts off an intercept c from the y-axis is y = mx + c
🔹 In particular, equation of a line whose slope is m and which passes through the origin is y = mx
Equations of a Straight Line
🔹 The equation of a line whose slope is m and which passes through the point (x1, y1) is (y-y1)=m(x-x1).
Equations of a Straight Line
🔹 The equation of a line passing through two points (x1, y1) and (x2, y2).
Intercept form of a Straight Line
The equation of a line cutting off intercepts a and b respectively from the x-axis and y-axis
Perpendicular form of a Straight Line
The equation of the line on which the length of the perpendicular from the origin is p and the perpendicular makes an angle α with the x-axis
Straight Line Distance from
The straight line through the point (x1, y1) and with inclination in θ and r is the distance of any point.
Equation of a Straight Line to a given parallel line
Equation of a line parallel to a given line ax + by + c = 0 is ax + by + k = 0 where k is a constant.
Equation of a Straight Line to a given perpendicular line
Equation of a line perpendicular to a given line ax + by + c = 0 is bx - ay + k = 0 where k is a constant.
Equation of a Straight Line through the point of intersection of two lines
where k (≠ 0) is an arbitrary constant.