Home › UP Board Class 10 › mathematics › linear_equations › Solve 1/x + 1/y = 1/3 and 1/x − 1/y = 1/12.
Solve 1/x + 1/y = 1/3 and 1/x − 1/y = 1/12.
Ax = 24/5, y = 8
Bx = 4, y = 6
Cx = 6, y = 4
Dx = 8, y = 24/5
Answer & Solution
Correct answer: A. x = 24/5, y = 8
Let u = 1/x, v = 1/y. u + v = 1/3 and u − v = 1/12. Adding: 2u = 5/12 ⇒ u = 5/24 ⇒ x = 24/5. Subtracting: 2v = 1/4 ⇒ v = 1/8 ⇒ y = 8.
Related questions
A two-digit number has digits whose sum is 9. Reversing the digits decreases the number byFive years ago A was thrice as old as B. Ten years later A will be twice as old as B. FindA boat travels 30 km downstream and 18 km upstream in 4 hours. It also travels 40 km downsA father is 30 years older than his son. After 5 years the father will be three times as oThe sum of two numbers is 25 and their difference is 5. Find them.A pair of equations gives a single solution iff:Solve 4x + 3y = 11 and 3x − 4y = 2.Find x and y in 5x − 7y = 2 and 7x − 5y = 22.