हिंदी

If 15x + 17y = 21 and 17x + 15y = 11, then find the value of x + y. - Algebra

Advertisements
Advertisements

प्रश्न

If 15x + 17y = 21 and 17x + 15y = 11, then find the value of x + y.

योग

उत्तर

The given equations are

15x + 17y = 21        ...(1)

17x + 15y = 11        ...(2)

Adding equations (1) and (2)

    15x + 17y = 21
+ 17x + 15y = 11  
    32x + 32y = 32

Dividing both sides by 32, we get

∴ x + y = 1

shaalaa.com
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
2019-2020 (March) Official 1 on shaalaa.com

संबंधित प्रश्न

If (9/2, 6) is lies on graph of 4x + ky = 12 then find value of k


Find five equations of lines which passes through (3, –5).


Find the value of k for which each of the following system of equations has infinitely many solutions :

\[kx + 3y = 2k + 1\]
\[2\left( k + 1 \right)x + 9y = 7k + 1\]


Find the value of k for which each of the following system of equations have no solution :

3x - 4y + 7 = 0

kx + 3y - 5 = 0


Find the value of k for which the following system of equations has a unique solution:

kx + 3y = 3

12x + ky = 6


Find the values of a and b for which the following system of equations has infinitely many solutions:

(2a - 1)x - 3y = 5

3x + (b - 2)y = 3


Solve for x and y: 

2x - `(3y)/4 = 3 ,5x = 2y + 7`


Solve for x and y:
0.4x + 0.3y = 1.7, 0.7x – 0.2y = 0.8.


Solve for x and y:
`x + y = a + b, ax - by = a^2 - b^2`


Solve for x and y:
`x/a + y/b = a + b, x/(a^2)+ y/(b^2) = 2`


Show that the following system of equations has a unique solution:
3x + 5y = 12,
5x + 3y = 4.
Also, find the solution of the given system of equations.


Find the value of k for which the system of equations has a unique solution:
x – ky = 2,
3x + 2y + 5=0.


5 chairs and 4 tables together cost ₹5600, while 4 chairs and 3 tables together cost
₹ 4340. Find the cost of each chair and that of each table


The sum of the digits of a two-digit number is 15. The number obtained by interchanging the digits exceeds the given number by 9. Find the number.


The sum of a two-digit number and the number obtained by reversing the order of its digits is 121, and the two digits differ by 3. Find the number,


A sailor goes 8 km downstream in 420 minutes and returns in 1 hour. Find the speed of the sailor in still water and the speed of the current .


A number consists of two digits whose sum is 10. If 18 is subtracted form the number, its digits are reversed. Find the number.


Find the value of k for which the system of equations 3x + 5y = 0 and kx + 10y = 0 has infinite nonzero solutions.


Read the following passage:


Lokesh, a production manager in Mumbai, hires a taxi everyday to go to his office. The taxi charges in Mumbai consists of a fixed charges together with the charges for the distance covered. His office is at a distance of 10 km from his home. For a distance of 10 km to his office, Lokesh paid ₹ 105. While coming back home, he took another roµte. He covered a distance of 15 km and the charges paid by him were ₹ 155.

Based on the above information, answer the following questions:

  1. What are the fixed charges?
  2. What are the charges per km?
  3. If fixed charges are ₹ 20 and charges per km are ₹ 10, then how much Lokesh have to pay for travelling a distance of 10 km? 
    OR
    Find the total amount paid by Lokesh for travelling 10 km from home to office and 25 km from office to home. [Fixed charges and charges per km are as in (i) and (ii).

Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×