The function f satisfies the functional equation $3f(x)+2f\left(\frac{x+59}{x-1}\right)=10x+30$ for all real x ≠ 1. The value of f(7) is

8 4 -8 11

4

$3f(x)+2f\left(\frac{x+59}{x-1}\right)=10x+30$ For $x = 7, 3 f(7)+ 2 f(11) = 70 +30 =100$ For $x =11, 3 f(11)+ 2 f(7) =140$ $⇒ f(7) = 4$