Question

What is the value of D, for Solving simultaneous equation X+Y=3
3X-2Y-4=0 by determinant method​

Answer 1

Answer:

$x + y = 3 \\ \\ 3x - 2y - 4 = 0 \\ 3x - 2y = 4 \\ \\ x + y = 3 \\ 3x - 2y = 4 \\ \\ |D| = |1 \: \: \: \: \: \: \: 1 | \\ \: \: \: \: \: \: \: \: \: \: \: \: \: | 3 \: \: - 2 | \\ |D| = (1 \times - 2) - (1 \times 3) \\ = - 2 - (3) \\ = - 2 - 3 \\ = \underline{ \underline{ - 5}}$