Solve for x and y: 9x - 2y = 108, 3x + 7y = 105

1.	Solve for x and y: 9x - 2y = 108, 3x + 7y = 105
Answer» The given system of equation can be written as: 9x - 2y = 108 ……(i) 3x + 7y = 105 ……(ii) On multiplying (i) by 7 and (ii) by 2, we get: 63x + 6x = 108 × 7 + 105 × 2 ⇒ 69x = 966 ⇒x = \(\frac{996}{69}= 14\) Now, substituting x = 14 in (i), we get: 9 × 14 – 2y = 108 ⇒ 2y = 126 – 108 ⇒ y = \(\frac{18}{2}= 9\) Hence, x = 14 and y = 9.

Answer»

The given system of equation can be written as:

9x - 2y = 108 ……(i)

3x + 7y = 105 ……(ii)

On multiplying (i) by 7 and (ii) by 2, we get:

63x + 6x = 108 × 7 + 105 × 2

⇒ 69x = 966

⇒x = \(\frac{996}{69}= 14\)

Now, substituting x = 14 in (i), we get:

9 × 14 – 2y = 108

⇒ 2y = 126 – 108

⇒ y = \(\frac{18}{2}= 9\)

Hence, x = 14 and y = 9.

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