Question

Lines 2x – by + 5 = 0 and ax + 3y = 2 are parallel to each other. Find the relation connecting a and b.

Answer 1

 2x – by + 5 = 0

by = 2x + 5

`y = (2x)/b + 5/b`

Slope of this line = `2/b`

ax + 3y = 2

3y = −ax + 2

`y = (-ax)/3 + 2/3`

Slope of this line =`(-a)/3`

Since, the lines are parallel, so the slopes of the two lines are equal.

∴ `2/b = (-a)/3`

ab = −6