Solve the following simultaneous equations by using Cramer's rule: 3x – y = 7 & x + 4y = 11

2. Solve the following simultaneous equations by using Cramer's rule:

3x – y = 7  & x + 4y = 11

Answer. The given equations are 3x – y = 7  & x + 4y = 11

D =	3	-1	=	(3 × 4) – (1 × - 1)	=	12 + 1	=	13
	1	4

Dx =	7	-1	=	(7× 4) – [11× (-1)]	=	28 + 11	=	39
	11	4

Dx =	3	7	=	(3×11) – [1× 7]	=	33 - 7	=	26
	1	11

By Cramer's Rule
x	=	Dx	=	39	=	3
		D		13
y	=	Dy	=	26	=	2
		D		13