Show graphically that each one of the following systems of equations is in-consistent (i.e. has no solution): 3a-5b=20 6a-10b=- 40
Show graphically that each one of the following systems of equations is in-consistent (i.e. has no solution): 3a-5b=20 6a-10b=- 40

Given,

3a-5b=20……. (i)

6a-10b=-40……. (ii)

From equation (i),

b=(3a-20)/5

When a=5, we have b=(3(5)-20)/5=-1

When a=0, we have b=(3(0)-20)/5=-4

Thus, we have the following table giving points on the line 3a-5b=20.

a 5 0
b -1 -4

From equation (ii),

Solve for b:

b=(6a+40)/10

So, when a=0

b=(6(0)+40)/10=4

And, when a=-5

b=(6(-5)+40)/10=1

Thus, we have the following table giving points on the line 6a-10b=-40

a 0 -5
b 4 1

 

Graph of the equations (i) and (ii) is given below:

From graph it is clear that, there is no common point between these two lines. Hence, the given systems of equations is in-consistent.