If (x - 1)2 + (y - 2)2 = (x – 1) (y - 2), where x and y are integers, then value of 2x + 3y is:
If (x - 1)2 + (y - 2)2 = (x – 1) (y - 2), where x and y are integers, then value of 2x + 3y is: Correct Answer 8
Given,
(x - 1)2 + (y - 2)2 = (x – 1) (y - 2)
Concept:/Formula:
(x – y)2 = k2
(x – y) = k or (–k)
x = (k + y) or (y – k)
Calculation:
(x -1)2 + (y - 2)2 = (x – 1) (y - 2)
Taking,
⇒ (x – 1)2 = (x – 1) (y – 2)
⇒ (x – 1) = (y – 2)
⇒ x – y = -2 + 1
⇒ x – y = (-1) ----(1)
Taking,
⇒ (y – 2)2 = (x – 1) (y – 2)
⇒ (y – 2) = (x – 1)
⇒ x – y = -2 + 1
⇒ x – y = (-1) ----(2)
Let y = 2 and x = 1, then
⇒ 1 – 2 = (-1)
(-1) = (-1) (satisfied)
Now,
2x + 3y
⇒ 2 × 1 + 3 × 2
⇒ 2 + 6
⇒ 8
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Feb 20, 2025