Question

To solve 2x+3y=12 & x-y=1 by determinant method, find D​

Answer 1

Solve by substitution method x + 2y = -1 and 2x - 3y = 12

The given equations are

⇒ x + 2y = – 1 … (i)

⇒ 2x – 3y = 12 …(ii)

From equation (i), we get

⇒ x = – 1 – 2y … (iii)

Putting x’s value in Equation (ii), we get

⇒ 2(- 1 – 2y) – 3y = 12

⇒ – 2 – 4y – 3y = 12

⇒ – 7y = 14

⇒ y = 14/- 7

⇒ y = – 2

Putting y’s value in equation (iii), we get

⇒ x = – 1 – 2y

⇒ x = – 1 – 2 × (- 2)

⇒ x = – 1 + 4

⇒ x = 3

Here, x = 3 and y = – 2.

Hence, the solution of the given equation is x = 3, y = – 2.