Jawabanmu

2014-03-01T18:05:19+07:00
F(2x -3) = 4x - 7
17 = 2x - 3
x = 10
f (17) = 4 . 10 - 7
= 33
7 = 2x - 3
x = 5
f (7) = 4 . 5 - 7
= 13 
f (17) - f (7) = 33 - 13 = 20
2014-03-01T18:42:58+07:00
F(2x-3) =4x-7
f(x) = 4(2x-3)-7
= 8x-12-7
= 8x -19
f(17) = 8.(17) - 19
f(17) =136-19 = 177
f(7) = 8(7)-19=37
f(17)-f(7)= 177-37=140
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