Find the equation of the line through the intersection of the lines 2x – 3y = 0 and 4x – 5y = 2 and which is perpendicular to the line x + 2y + 1 = 0.
Find the equation of the line through the intersection of the lines 2x – 3y = 0 and 4x – 5y = 2 and which is perpendicular to the line x + 2y + 1 = 0.

Answer : Suppose the given two lines intersect at a point P(x1, y1). Then, (x1, y1) satisfies each of the given equations.

2x – 3y = 0 …(i) 4x – 5y = 2 …(ii)

Now, we find the point of intersection of eq. (i) and (ii) Multiply the eq. (i) by 2, we get

4x – 6y = 0 …(iii)

On subtracting eq. (iii) from (ii), we get 4x – 5y – 4x + 6y = 2 – 0

⇒ y = 2

Putting the value of y in eq. (i), we get

2x – 3(2) = 0

⇒ 2x – 6 = 0

⇒ 2x = 6

⇒ x = 3

Hence, the point of intersection P(x1, y1) is (3, 2)