diketahui rumus fungsi f(x)=3x+5. Jika f(k)=-1 , maka nilai k adalah

f(x) = 3x + 5
f(k) = - 1

f(k) = 3k + 5
- 1 = 3k + 5
3k = - 5 - 1
3k = - 6
k = - 6 / 3
k = - 2