Advertisements
Advertisements
प्रश्न
The value of expression mx - ny is 3 when x = 5 and y = 6. And its value is 8 when x = 6 and y = 5. Find the values of m and n.
Advertisements
उत्तर
The value of expression mx - ny is 3 when x = 5 and y = 6.
⇒ 5m - 6n = 3 .....(1)
The value of expression mx - ny is 8 when x = 6 and y = 5.
⇒ 6m - 5n = 8 ....(2)
Multiply equation (1) by 6 and equation (2) by 5, We get:
30m - 36n = 18 ....(3)
30m - 25n = 40 .....(4)
Subtracting equation (4) from (3)
30m - 36n = 18
- 30m - 25n = 40
- + -
- 11n = - 22
n = 2
Substituting n = 2 in equation (1), we get
5m - 6(2) = 3
⇒ 5m = 15
⇒ m = 3
∴ Solution is m = 3 and n = 2.
APPEARS IN
संबंधित प्रश्न
For solving pair of equation, in this exercise use the method of elimination by equating coefficients :
13 + 2y = 9x
3y = 7x
For solving pair of equation, in this exercise use the method of elimination by equating coefficients :
`[ x - y ]/6 = 2( 4 - x )`
2x + y = 3( x - 4 )
For solving pair of equation, in this exercise use the method of elimination by equating coefficients :
13x+ 11y = 70
11x + 13y = 74
Solve the following simultaneous equations :
6x + 3y = 7xy
3x + 9y = 11xy
Solve the following simultaneous equations :
2(3u - v) = 5uv
2(u + 3v) = 5uv
Solve the following simultaneous equations:
65x - 33y = 97
33x - 65y = 1
Seven more than a 2-digit number is equal to two less than the number obtained by reversing the digits. The sum of the digits is 5. Find the number.
If 2 is added to the numerator and denominator it becomes `(9)/(10)` and if 3 is subtracted from the numerator and denominator it becomes `(4)/(5) `Find the fraction.
If 1 is added to the denominator of a fraction, the fraction becomes `(1)/(2)`. If 1 is added to the numerator of the fraction, the fraction becomes 1. Find the fraction.
Salman and Kirti start at the same time from two places 28 km apart. If they walk in the same direction, Salman overtakes Kirti in 28 hours but if they walk in the opposite directions, they meet in 4 hours. Find their speeds (in km/h).
