Question

Diketahui f(x) = ax+b
jika f(2) = 8 dan f(1) = 5
tentukan f(5)

Answer 1

2a + b = 8
a + b = 5
pakek metode eliminasi dan subsitusi  jadi b=1/2 , a = 9/2
f(5) = 9/2.5 + 1/2
f = 46/2
f = 23

Answer 2

F(x) = ax+b
f(2) = 2a + b
f(2) = 8
f(1) = 1a +b
f(1) = 5
f(5) = ?

8 = 2a + b
5 = a + b
________________ -
3 = a
a = 3

f(2) = 2a+b
8= 2(3)+b
8 = 6 +b
b= 8 - 6
b = 2

f(5) = 5a+b
f(5) = 5(3) + 2
f(5) = 15 + 2
f(5) = 17