Question

1. Solve the following simultaneous equation by the Cramer’s rule
3x -2y = 3 and 2x + y = 16

Answer 1

Answer:

3x- 2y= 3 (1) and

2x+y =16 (2)

D=

$|3 \: \: \: \: \: \: - 2 \: \\ \: \: \: 2 \: \: \: \: \: \: \: \: \: \: \: \: 1|$

=(3×1)-(-2×2)

=3 + 4

=7

Dx =

$|3 \: - 2 \\ 16 \: \: \: \: 1|$

=(3×1)-(-2×16)

= 3 + 32

= 35

Dy =

$|3 \: \: \: \: \: 3 \\ 2 \: \: \: 16 |$

= (3×16)-(3×2)

= 48-6

= 42

X=

$\frac{dx}{d} = \frac{35}{7} = 5$

Y=

$\frac{dy}{d} = \frac{42}{7} = 6$