Question

For simultaneous equations in variables x and y, Dx= 27 , Dy=18 , D = 3,
then what is y ?

(a) 6 (b) 9 (c) 1/6 (d) 1/9​

Answer 1

Option(a) 6.

Given :-

• For simultaneous equations in variables x and y.

• Dx = 27 , Dy = 18 , D = 3.

To Find :-

• Value of y.

Solution :-

According to Cramer's rule,

• x = Dx/D OR y = Dy/D

[ First solve for "x" ]

↪ x = 27/3

↪ x = 9

[ Now, solve for "y" ]

↪ y = 18/3

↪ y = 6

Hence,

• The value of y is 6.

For information:

• a² - b² = (a - b)(a - b)
• (a + b)² = a² + 2ab + b²
• a² + b² = (a + b)² - 2ab
• (a - b)² = a² - 2ab + b²
• (a + b)³ = a³ + 3a²b + 3ab² + b³
• (a - b)³ = a³ - 3a²b + 3ab² - b³
• a³ - b³ = (a - b)(a² + ab + b²)
• a³ + b³ = (a + b)(a² - ab + b²)

Answer 2

Answer:

♣️Question

For simultaneous equations in variables x and y, Dx= 27 , Dy=18 , D = 3,

then what is y ?

(a) 6 (b) 9 (c) 1/6 (d) 1/9

♣️ AnSwEr

(a) 6

♣️ Explanation

According to the charmer's rule

$x = \frac{dx}{d} \: or \: y = \frac{dy}{d}$

Solving for x

$x = \frac{27}{3}$

$x = 9$

$\huge \bf \: x = 9$

Solving for y

$y = \frac{18}{3}$

$y = 6$

$\huge \bf \: y = 6$