Solve each of the following systems of equations by using the method of cross multiplication:
x+2y+1=0,
2x−3y−12=0.
x+2y+1=0……….(i)
2x−3y−12=0……….. (ii)
Here a1=1,b1=2,c1=1
a2=2,b2=−3,c2=−12
By cross multiplication method,
x−24+3=−y−12−2=1−3−4
x−21=−y−14=1−7
Now,
x−21=1−7
=x=3
And,
−y−14=1−7
=y=−2
The solution of the given system of equation is 3 and -2 respectively.