diketahui g(x)=ax+c jika h(3)=11 dan h(7)=19 tentukan nilai dari h(-8)

g(x) = ax + c
h(3) = a(3) + c = 11
h(7) = a(7) + c = 19
..
3a + c = 11
7a + c = 19
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- 4a = - 8
a = -8/-4
a = 2

3a + c = 11
3(2) + c = 11
6 + c = 11
c = 11 - 6
c = 5

bentuk fungsi baru
g(x) = ax + c
g(x)= 2x + 5

h(-8) = 2(-8) + 5
= -16 + 5
= - 11