Question

Pada pemetaan f:x-> ax+b, bila f(2)=1 dan f(7)=16 maka nilai a-b

Answer 1

F(x) = ax + b
f(2) → 2a + b = 1
f(7) → 7a + b = 16

2a + b = 1
7a + b = 16
—————— –
-5a = - 15
a = 3

2a + b = 1
2(3) + b = 1
6 + b = 1
b = 1 - 6
b = - 5

Jadi, a - b = 3 - (-5) = 3 + 5 = 8