Solve the following systems of linear equations by Cramer’s rule:

2x – y = – 2


3x + 4y = 3

Given : – Two equations 2x – y = – 2 and 3x + 4y = 3


Tip: - Theorem – Cramer’s Rule


Let there be a system of n simultaneous linear equations and with n unknown given by







and let Dj be the determinant obtained from D after replacing the jth column by



Then,


provided that D ≠ 0


Now, here we have


2x – y = – 2


3x + 4y = 3


So by comparing with the theorem, let's find D, D1 and D2



Solving determinant, expanding along 1st row


D = 2(4) – (3)( – 1)


D = 8 + 3


D = 11


Again,



Solving determinant, expanding along 1st row


D1 = – 2(4) – (3)( – 1)


D1 = – 8 + 3


D1 = – 5


and



Solving determinant, expanding along 1st row


D2 = 3(2) – ( – 2)(3)


D2 = 6 + 6


D2 = 12


Thus by Cramer’s Rule, we have




and




5