If a, b and c are positive integers such that $a^2 + b^2 = 82$ and $b^2 + c^2 = 65$, then the value of 2a + 7b − 3c is:
Answer & explanation
Correct answer: option 4
$a^2 + b^2 = 82$
$b^2 + c^2 = 65$,
Then the value of 2a + 7b − 3c = ?
Put the value of a = 9 , b = 1 and c = 8
2a + 7b − 3c = 2×9 + 7×1 − 3×8 = 18 + 7 - 24
2a + 7b − 3c = 1