Question

Choose correct alternative for the following question.
For simultaneous equations in variables x and y, D_x = 49, D_y = –63, D = 7 then what is x?

Options

• 7

• – 7

• `1/7`

• `(-1)/7`

Answer 1

7

Explanation:

Given D_x ​= 49, D_y ​= −63, D = 7

From cramer's rule

x = `D_x/D`, y = `D_y/D`

⇒ x = `49/7`

⇒ x = 7