Question

QUIZ

f(x) = 12x + 13 - 10
f(a) = 111

Nilai a adalah?
A. 9
B. 10
C. 11
D. 15
Berikan pembuktiannya!
____
Aduh :)​

Answer 1

~ Fungsi ~
f(x) = 12x + 13 - 10
f(x) = 12x + 3

f(a) = 111

• Nilai a
Ganti x menjadi a
f(x) = 12x + 3
f(a) = 12a + 3
111 = 12a + 3
12a = 111 - 3
12a = 108
a = 108/12
a = 9

• Pembuktian
f(x) = 12x + 3
f(x) = 12(9) + 3
f(x) = 108 + 3
f(x) = 111

Answer 2

f(x) = 12x + 13 - 10

f(a) = 12x + 13 - 10 = 111

f(a) = 12x + 3 = 111

f(a) = 12x = 111 - 3

f(a) = 12x = 108

f(a) = x = 108/12

f(a) = x = 9

f(a) = a = 9

Pembuktian :

12x + 13 - 10

12(9) + 13 - 10

108 + 13 - 10

121 - 10

111