Question

Fungsi h didefinisikan dengan rumus h (x) = ax + b.
Jika h (5) = -8 dan h (-2) = 13, nilai h (3) adalah

Answer 1

H(5) = -8
→ x dalam fungsi h(x) diganti angka 5, jadi:
a(5) + b = -8
5a + b = -8 .........(i)

h(-2) = 13
→ x dalam fungsi h(x) diganti angka -2, jadi:
a(-2) + b = 13
-2a + b = 13 .........(ii)

→ eliminasi pers. (i) dan (ii)
5a + b = -8
-2a + b = 13
——————— -
7a = -21
a = -3

→ substitusi
5a + b = -8
5(-3) + b = -8
b = -8 + 15
b = 7

h(3)
= -3(3) + 7
= -9 + 7
= -2