Method 1:

Step 1: Note down the given points as well as assign these points with the variables

EXAMPLE: ( 7, 4 ) assign this point with (x_1, y_1)

( 2, 0 ) assign this point with (x_2,y_2)

................etc

Step 2: Calculate gradient or slope(m) from two points

FORMULA: \frac{y-change}{x-change},

or \frac{y_2 - y_1}{x_2 - x_1}

EXAMPLE: Slope of A(7, 4) and B(2, 0 )

\frac{4-0}{7-2} = \frac{4}{5}

Step 3: Substitute either values slope(m) and any one point into the equation of a straight line.

FORMULA: Equation of a straight line

y - y_1 = m(x - x_1)

Where m = slope and ( x_1, y_1) = any point

EXAMPLE: I took (2, 0) as a point and m = \frac{4}{5}

y - 0 = \frac{4}{5} ( x - 2)

5y = 4x - 8

Step 4: Simplify and make the equation in the form of Ax + By + C =0

Method 2:

Step 1: Note down the given points as well as assign these points with the variables

EXAMPLE: ( 7, 4 ) assign this point with (x_1, y_1)

( 2, 0 ) assign this point with (x_2, y_3)

................etc

Step 2: Substitute either given points in the formula.

FORMULA:

(y_1-y_2)x+\left(x_2-x_1)y+(x_1y_2-x_2y_1)\right) = 0

Step 3: Simplify and make the equation in the form of Ax+ By + C =0