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### General form of the equation of a line

The equation of a straight line can be written in many different forms. One of the common forms is the general form.
Ax + By + C = 0
is the general form of the equation of a straight line

The following equations are in said to be in general form:
• x + 3y + 4 = 0
• 10x + 15y + 4 = 0
• x - 10y = 0 (here 'C' is zero)
• x + 3 = 0 (here 'B' is zero)
• 4y + 2 = 0 (here 'A' is zero)
An equation written in general form should not start with a negative number, that is, the value of the coefficient of x (represented by A) should not be a negative number.

The following equations are not in the general form:
• x + 3y = 4 (the number 4 should be on the left hand side)
• -x - 10y = 0 (x should not be negative)
• x + 3 + y = 0 (the correct order is x, then y then the number)

Some equations in the general form, with their graphs:
• x + 3y + 4 = 0
•  10x + 15y + 4 = 0
Getting the x and y intercepts and slope from an equation in the general form
An equation written in the general form Ax + By + C = 0, has
• x-intercept = -C/A
• y-intercept = -C/B
• slope = -A/B