Suatu fungsi f dirumuskan dgn f(x)=ax+b. Jika f(4)=3 dan f(5)= -9. Nilai 3a+2b?

f(x) = ax+b
f(4) = 4a + b = 3
f(5) = 5a + b = -9
dieliminasi, sehingga menjadi -a = 12 maka a = -12

disubstitusikan
4a + b = 3
4(-12) + b = 3
b = 3+48
b = 51

3a + 2b
= 3(-12) + 2(51)
= -36 + 102
= 66

f(4) = 4a + b = 3
f(5) = 5a + b = -9
-a = 12
a = -12
4a + b = 3
-48 + b= 3
b = 3 + 48
b = 51

3a + 2b = 3. -12 + 2. 51
= -36 + 102
= 66
semoga membantu
jadikan yg terbaik yahh