tolong bantu ngerjain soalnya nya pake cara

maaf klo salah atau g jelas yaaa

f(x) = 2x+3
f(k) = 9
f(k) = 2k+3 = 9
= 2k = 9-3
= 2k = 6
= k = 6/2
= k = 3

semoga membantu