Question

Solve it 9x-4y=2000
7x-3y=2000

Answer 1

hope it help u.........

Answer 2

Answer :-

x = 2000

y = 4000

Explanation :-

Given pair of linear equations

9x - 4y = 2000 ---eq(1)

7x - 3y = 2000---eq(2)

LCM of coefficients of y i.e 4 and 3 is 12

So Multiply eq(1) with 3 and eq(2) with 4

After multipliplying pair of linear equation we have

27x - 12y = 6000 ---eq(3)

28x - 12y = 8000 ---eq(4)

Subtrating eq(2) from eq(1)

⇒ 27x - 12y - (28x - 12y) = 6000 - 8000

⇒ 27x - 12y - 28x + 12y = - 2000

⇒ - x = - 2000

⇒ x = 2000

Substitute x = 2000 in eq(1)

⇒ 9x - 4y = 2000

⇒ 9(2000) - 4y = 2000

⇒ 18000 - 4y = 2000

⇒ 18000 - 2000 = 4y

⇒ 16000 = 4y

⇒ 16000/4 = y

⇒ 4000 = y

⇒ y = 4000

∴ x = 2000 and y = 4000

Note :-

The method used to solve this question is ELIMINATION METHOD.