Advertisements
Advertisements
प्रश्न
Solve the following pairs of equations:
`(xy)/(x + y) = (6)/(5)`
`(xy)/(y - x)` = 6
Where x + y ≠ 0 and y - x ≠ 0
Advertisements
उत्तर
`(xy)/(x + y) = (6)/(5)`
⇒ `(x + y)/(xy) = (5)/(6)`
⇒ `(1)/y + (1)/x = (5)/(6)` ....(i)
`(xy)/(y - x)` = 6
⇒ `(y - x)/(xy)` = 6
⇒ `(1)/x + (1)/y = (1)/(6)` ....(ii)
Adding eqns. (i) and (ii), we get
`(2)/x` = 1
⇒ x = 2
⇒ `(1)/y + (1)/(2) = (5)/(6)`
⇒ `(1)/y = (5)/(6) - (1)/(2)`
= `(5 - 3)/(6)`
= `(2)/(6)`
= `(1)/(3)`
⇒ y = 3
Thus, the solution set is (2, 3).
APPEARS IN
संबंधित प्रश्न
For solving pair of equation, in this exercise use the method of elimination by equating coefficients:
y = 2x - 6; y = 0
For solving pair of equation, in this exercise use the method of elimination by equating coefficients :
2x − 3y − 3 = 0
`[2x]/3 + 4y + 1/2` = 0
Find the value of m, if x = 2, y = 1 is a solution of the equation 2x + 3y = m.
10% of x + 20% of y = 24
3x - y = 20
If 2x + y = 23 and 4x - y = 19 : find the value of x - 3y and 5y - 2x.
The length of a rectangle is twice its width. If its perimeter is 30 units, find its dimensions.
In a two-digit number, the sum of the digits is 7. The difference of the number obtained by reversing the digits and the number itself is 9. Find the number.
The ratio of two numbers is `(2)/(5)`. If 4 is added in first and 32 is subtracted from the second, the ratio becomes the reciprocal of the original ratio. Find the numbers.
In a triangle, the sum of two angles is equal to the third angle. If the difference between these two angles is 20°, determine all the angles.
Two mobiles S1 and S2 are sold for Rs. 10,490 making 4% profit on S1 and 6% on S2. If the two mobiles are sold for Rs.10,510, a profit of 6% is made on S1 and 4% on S2. Find the cost price of both the mobiles.
