A linear equation is an equation for a straight line.
There are many ways of writing linear equations. They usually have constants (like “3” or “c”) and must have simple variables (like “x” or “y”).
The variables (like “x” or “y”) in Linear Equations do NOT have:
Exponents (like the 2 in x2)
Square roots, cube roots, etc
The most common form is the slope-intercept equation of a straight line:
y = mx + b
m = slope or gradient
b = y intercept
Another common one is the Point-Slope Form of the equation of a straight line:
y − y1 = m(x − x1)
There is General Form of the equation of a straight line:
Ax + By + C = 0
(A and B cannot both be 0)