If one of the lines represented by a x 2 + 2 h x y + b y 2 = 0 passes through ( 2 , 3 ) and the other passes…

If one of the lines represented by ax2+2hxy+by2=0 passes through (2,3) and the other passes through (4,5), then a+2 h+b equals
  1. 0
  2. 1
  3. 2
  4. -1

Solution

Given that: ax2+2hxy+by2=0

Passing through (2,3) &(4,5)

Given equation passing through (0,0)

As we know, Equation of line passing through two given points y-y1=y2-y1x2-x1(x-x1)

Equation of the line through (0,0) & (2,3)y=32x

3x-2y=0

Equation of the line through (0,0) & (4,5) : y=54x

5x-4y=0

Here, the pair of straight lines is (3x-2y)(5x-4y)=0

15x2-22xy+8y2=0

a=15, h=-11, b=8

a+2h+b=15-22+8=1

Asked in: AP EAMCET 2021 (20 Aug Shift 2)

Practice more Pair of Lines questions on Aicharya