1.

If 9x + 7y = 130, 2x – y = 11, then what will be the value of (x + y)?1. 152. 143. 214. 16

Answer» Correct Answer - Option 4 : 16

Given:

9x + 7y = 130    

2x – y = 11    

Calculation:

Our given equation are 

9x + 7y = 130      ----(1)

2x – y = 11      ----(2)

Multiply eq (2) with 7 and equation (1) with 1

9x + 7y = 130      ----(3)

7(2x – y) = 11 × 7 = 77     ----(4)

Add equation (4) and equation (3)

9x + 7y + 14x – 7y = 130 + 77

⇒ 23x = 207

⇒ x = 207/23 = 9

Now, from eq (2)

2x – y = 11

⇒ 2 × 9 – y = 11

⇒ y = 18 – 11 = 7

Now, x + y = 9 + 7 = 16

∴ The required answer is 16



Discussion

No Comment Found

Related InterviewSolutions