Question

Tolong dijawab plisss a, b, c saja plis

Answer 1

Verified answer

F(x) = ax+b
f(2) = 2a+b=13 (1)
f(5) = 5a+b=22 (2)


eleminasikan
2a+b=13
5a+b= 22
__________ -
-3a =-9
a= 3

2.3+b=13
6+b=13
b= 13-6
b= 7

A. nilai A= 3 dan nilai B = 7
B. bentuk fungsinya —> f(x)=3x+7
C. f(-8) = 3.-8+7
= -24+7
= -17

Answer 2

Kode : 8.2.2 [Kelas 8 Matematika Bab 2 Fungsi ]
Kelas : 8
Mapel : Matematika
Kategori : Bab 2 Fungsi

f(x) = ax + b

diketahui
f(2) = 13   dan    f(5) = 22, maka

f(2) = 2a + b = 13
f(5) = 5a + b = 22
        -------------------- (-)
             3a = 9
               a = 3
2a + b = 13
2(3) + b = 13
b = 13 - 6
b = 7

jadi bentuk fungsi f adalah
f(x) = 3x + 7

c. Byangan dari (-8)
f(-8) = 3(-8) + 7
f(-8) = -24 + 7
f(-8) = -17

d.
f(-3) = 3(-3) + 7
f(-3) = -2

e.
3f(4) - 4f(-1)
= 3(3(4) + 7) - 4(3(-1) + 7)
= 3 (12 + 7) - 4(-3 + 7)
= 57 - 16
= 41

f.
2f(-1) - 5f(0)
= 2(3(-1) + 7) - 5(3(0) + 7)
= 2(-3 + 7) - 5(7)
= 8 - 35
= -27