1.Diketahui F(x)=ax+b, f(-2)=-4 dan f(-6)=12 tentukan bentuk fungsi f(x) dan f(25) 2. Diketahui f(x)=ax+b, f(7/5)=7 dan f(1/5)=13 tentukan nilai A. a dan x B. t

1. f(-2)= -2a + b = -4
f(-6)=-6a + b = 12
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4a = -16
a = -4

f(-2) = -2a + b = -4
-2(-4) + b = -4
8 + b = -4
b = -4 - 8
b =-12

Bentuk fungsi = f(x) = -4x + -12

f(25) = -4(25) + (-12)
=-100 + (-12)
=-112


2. f(7/5) = 7/5a + b =7
f(1/5) = 1/5a + b = 13
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6/5a = -6
a = -6 : 6/5
a = -6 x 5/6
a = -5
nilai x = 7/5 dan 1/5
nilai b = f(1/5) = 1/5 (-5) + b = 13
-1 + b = 13
b = 13 +1
b = 14

Bentuk fungsinya = f(x) = -5x +14

f(-3/5) = -3/5(-5) + 14
= 3 + 14
= 17