parallel line equation of the line

Question

Write an equation of the line that passes through the
given point and is parallel to the given line.

(1,-1);y=-3x+7

Answer 1

Slope - intercept form line equation is y = mx + b, where m is slope and b is y - intercept.

The line equation is y = - 3x + 7.

Comapare the equation with slope - intercept form.

Slope (m) = - 3

Because the parallel lines have same slopes, the slope of parallel line through the point (1, - 1) is - 3.

Now the parallel line equation is y = - 3x + b.

Find the y - intercept by substituting the point in the parallel line equation say (x, y) = (1, - 1).

- 1 = (- 3)(1) + b

b = - 1 + 3

⇒ b = 2

The parallel line equation is y = - 3x + 2.