NIMCET 2014 — Mathematics PYQ
NIMCET | Mathematics | 2014If x and y are positive real numbers satisfying the system of equations x2+yxy=336 and y2+xxy=112, then x+y is:
Choose the correct answer:
- A.
448
- B.
224
- C.
20
(Correct Answer) - D.
40
20
Explanation
Solution
1. Given Equations:
-
x2+yxy=336
-
y2+xxy=112
2. Simplifying the Equations:
Divide the first equation by x:
Divide the second equation by y:
3. Finding the Relationship between x and y:
Since the left-hand sides of equations (1) and (2) are identical (xx+yy), we can equate the right-hand sides:
Squaring both sides:
4. Solving for y and x:
Substitute the values from equations (3) and (4) into equation (1):
Since y must be a positive real number:
-
y=2
-
Using x=9y, we get x=9(2)=18
5. Final Calculation:
Correct Option: 3 (20)
Explanation
Solution
1. Given Equations:
-
x2+yxy=336
-
y2+xxy=112
2. Simplifying the Equations:
Divide the first equation by x:
Divide the second equation by y:
3. Finding the Relationship between x and y:
Since the left-hand sides of equations (1) and (2) are identical (xx+yy), we can equate the right-hand sides:
Squaring both sides:
4. Solving for y and x:
Substitute the values from equations (3) and (4) into equation (1):
Since y must be a positive real number:
-
y=2
-
Using x=9y, we get x=9(2)=18
5. Final Calculation:
Correct Option: 3 (20)