If a + b = 24 and $a^2 + b^2 = 306 $, where a > b, then the value of 4a - 5b is :

18 20 12 15

15

If a + b = 24 $a^2 + b^2 = 306 $ where a > b, then the value of 4a - 5b= ? Put the value of a = 15 and b = 9 (These values will satisfy the given equation) 4a – 5b = 4 × 15 – 5 × 9 = 60 – 45 = 15