Mathematics · essential
Condition for parallel lines using coefficients for JEE
Straight line: Various forms of equations of a line, intersection of lines, angles between two lines
Formula
\(a_1b_2-a_2b_1=0\)
Variables: Lines are \(a_1x+b_1y+c_1=0\) and \(a_2x+b_2y+c_2=0\).
Conditions: For distinct parallel lines, additionally \(\frac{a_1}{a_2}=\frac{b_1}{b_2}\ne \frac{c_1}{c_2}\).
Parallelism test in general form.