Question

If 18x + 17 y = 35 and 17x +18 y = 35, then x - y =
(a) 0
(b) 1
(c)35
(d) 70​

Answer 1

Option A:

x – y = 0

Solution:

Given equations are

18x + 17y = 35 – – – – (1)

17x + 18y = 35 – – – – (2)

To solve the equations:

Multiply equation (1) by 17 and equation (2) by 18.

(1) × 17 ⇒ 306x + 289y = 595  – – – – (3)

(2) × 18 ⇒ 306x + 324y = 630  – – – – (4)

Subtract (4) from (3), we get

306x + 289y – 306x – 324y = 595 – 630

–35y = –35

Divide by –35 on both side of the equation.

y = 1

Substitute y = 1 in equation (1), we get

18x + 17y = 35

18x + 17(1) = 35

18x = 35 – 17

18x = 18

x = 1

To find x – y:

x – y = 1 – 1 = 0

x – y = 0

Option A is the correct answer.

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https://brainly.in/question/8860913

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Answer 2

The required 'option a) 0' is correct.

Step-by-step explanation:

The given equations are:

18x + 17 y = 35                      ......... (1)

and 17x + 18 y = 35               ......... (2)

To find, the value of x - y = ?

Subtracting (1) from (2), we get

18x + 17 y - ( 17x + 18 y) = 35 - 35      

⇒ 18x + 17 y - 17x - 18 y = 35 - 35  

⇒ (18x - 17x) + (17 y - 18y) = 0

⇒ x - y = 0

∴ The value of x - y = 0

Thus, the required 'option a) 0' is correct.