Selesaikan Soal No.10 Di atas Guys pakai Cara yah bantuin

f(x) = 6x - 3
g(x) = 5x + 4

fog(x) = f(g(x)
fog(x) = 6(5x + 4) - 3
fog(x) = 30x + 24 - 3
fog(x) = 30x + 21

Jika fog(a) = 81, berapa nilai a?
fog(a) = 81
30a + 21 = 81
30a = 81 - 21
30a = 60
a = 60/30
a = 2
JAWABAN D

f(x)=6x-3
g(x)=5x+4
fog(x) = f(g(x))
=f(5x+4)
=6(5x+4)-3
=30x+24-3
=30x+21

fog(a) = 81
30a+21 =81
30a = 81-21
30a = 60
a= 60/30=2