Question

Prove that the lines 3x-4y+5=0,7x-8y+5=0 and 4x+5y=5 are concurrent?

Answer 1

The point of intersection of  3x-4y+5=0,7x-8y+5=0 is (5,5)

Now calculate the value of the image attached..

If it is zero, they are concurrent

a1 = 3 
b1 = -4
c1 = 5 

and the similarity continues